I want to make Header position:fixed. So I've written CSS for  .Header {  position:fixed;  top: 0; left: 0; width: 100%; }  in first page there is no problem. If page is more than one then overlapping header by table. I've tried to to give table margin-top but not working.
I want to make header fixed like image down below:

My code:
        <style>
            @page {
              size: 8.27in 5.8in Portrait;
            }
            body {
              font-family: Consolas, Courier, sans-serif;
              font-size: 14px;
              margin: 0;
            }
            label {
              font-weight: 600;
              line-height: 30px;
            }
            ul {
              list-style: none;
              padding: 0;
            }
            table {
              margin: 8px 0;
              width: 100%;
            }
            .printTable table thead {
              background: #ddd;
            }
            .printTable table,
            .printTable th,
            .printTable td {
              border: 1px solid #a9a6a6;
              border-collapse: collapse;
              padding: 5px 8px;
              text-align: left;
            }
            .printTable table tr th:first-child {
              width: 7%;
            }
            .hide {
              display: none;
            }
            .Header h4,
            .Header h2 {
              margin-bottom: 4px;
              margin-top: 4px;
            }
            img {
              width: 130px;
              height: 140px;
            }
            .PrintFoot p {
              margin: 0 0 3px 0;
            }
            .Header {
              position: fixed;
              top: 0;
              left: 0;
              width: 100%;
            }
            /* .printTable {
                   margin-top: 300px !important;
            }*/
            </style>
          <div class="main-div">
                <div class="Header">
                    <div style="overflow: auto;">
                        <div style="width: 20%; float: left;">
                            <img src="https://www.opticcell.com/wp-content/uploads/logo-patriot-250x250.png">
                        </div>
                        <div style="width: 70%; float: left; text-align: center; font-family:'Lato', sans-serif;">
                            <div style="padding-left: 20px;">
                                <h2> {Company} </h2>
                                <h2 style="font-size: 16px;"> {MailName} </h2>
                                <h4> {Address}</h4>
                                <h4> {Phone}</h4>
                                <strong>PAN :</strong> {pan}
                                <h4>{InvoiceCopy}</h4>
                            </div>
                        </div>
                        <div style="width: 20%;"></div>
                    </div>
                    <div style="overflow: auto;">
                        <div style="width: 50%; float: left; text-align:left;">
                            <strong>Invoice No :</strong> {Invoice}
                            <br>
                            <strong>Patient ID :</strong> {PatientID}
                            <br>
                            <strong>Patient Name :</strong> {PatientName}
                            <br>
                            <strong>Age/Sex: </strong> {PatientAge}
                            <br>
                            <strong>Address :</strong> {PatientAddress}
                            <br>
                            <strong>Contact :</strong> {contact}
                            <br>
                            <strong>Party PAN :</strong> {party}
                            <br>
                            <strong>IP no. : </strong> {ipno}
                        </div>
                        <div style="width: 50%; float: left; text-align: right;">
                            <strong>Date :</strong> {Date}
                            <br>
                            <strong>Claim Code :</strong> {ClaimID}
                            <br>
                            <strong>Billing Type :</strong> {Type}
                            <br>
                            <strong>Bill To :</strong> {AccountLedger}
                            <br>
                            <strong>Payment mode :</strong> {Type}
                            <br>
                            <strong>Refer By:</strong> {refer}
                            <br>
                            <strong>Location:</strong> {location}
                        </div>
                    </div>
                </div>
                <div class="MiddlePart">
                    <div class="printTable">
                        <table class="table table-bordered table-striped">
                            <thead>
                                <tr>
                                    <th>S.N.</th>
                                    <th>Particular</th>
                                    <th>Qty</th>
                                    <th>Rate</th>
                                    <th>Net Total</th>
                                </tr>
                            </thead>
                            <tbody>
                                <tr>
                                    <td>S.N.</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>1</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>2</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>3</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>4</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>5</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>6</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>7</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>8</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>9</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>10</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>11</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>12</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>13</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>14</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>15</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>16</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>17</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>18</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>19</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>20</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>21</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>22</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>23</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>24</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>25</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                                <tr>
                                    <td>26</td>
                                    <td>Particular</td>
                                    <td>Qty</td>
                                    <td>Rate</td>
                                    <td>Net Total</td>
                                </tr>
                            </tbody>
                        </table>
                    </div>
                    <div style="overflow: auto;">
                        <div style="width: 68%; float: left;">
                            <strong>Pre-Deposit :</strong> {preDepo}
                            <br>
                            <strong>New Deposit :</strong> {newDepo}
                            <br>
                            <strong>New Deposit :</strong> {newDepo}
                            <br>
                            <strong>In Words:  </strong> {InWords}
                        </div>
                        <div style="width: 32%; float: left; text-align: right;">
                            <strong>Bill Total:  </strong> {BillTotal}
                            <br>
                            <strong>Discount  : </strong> {Discount}
                            <br>
                            <strong>Net Total  : </strong> {NetTotal}
                            <br>
                            <strong>Net Total  : </strong> {NetTotal}
                            <br>
                            <strong>Net Total  : </strong> {narration}
                            <br>
                            <strong>Enter By :</strong> {User}
                        </div>
                    </div>
                </div>
                <div class="PrintFoot" style="margin-top: 10px;">
                    <p><strong>Lab Login :</strong> {LoginCredential}</p>
                    <p><strong>Print Date : </strong> Admin {PrintDate}</p>
                    <p style="margin: 15px 0;">
                        <strong>Note : </strong> 
                        If there are any, kindly bring all previous reports and documents on the day of the appointment or treatment. There will be no refunds without original invoice. </p>
                     <p style="text-align: center;">Get Well Soon !!</p>
                </div>
            </div>
            <!-- end snippet -->