PHP | CSV data not loaded inside the db

Question

I have a small problem with a form that imports the data inside a .csv file inside my db.

Inside my code I have an if loop that checks if the email parameter inside the .csv file already exists in the db, it returns an error message, otherwise it executes the insert query.

I always get the success message but the records are never registered inside the table.

Running the insert query var_dump, I get:

object(mysqli_stmt)#4 (10) { ["affected_rows"]=> NULL ["insert_id"]=> NULL ["num_rows"]=> NULL ["param_count"]=> NULL ["field_count"]=> NULL ["errno"]=> NULL ["error"]=> NULL ["error_list"]=> NULL ["sqlstate"]=> NULL ["id"]=> NULL }

code:

<?php
include('../connection/cnt.php');
$info = array();

if(isset($_POST["submit"]))
{
    $file = $_FILES['file']['tmp_name'];
    $handle = fopen($file, "r");
    $c = 0;
    $i = 0;

    while(($filesop = fgetcsv($handle, 1000, ",")) !== false)
    {
        $i++;
        if($i === 1) continue;

        $username = $filesop[0];
        $name = $filesop[1];
        $surname = $filesop[2];
        $email = $filesop[3];

        /*CHECK IF EMAIL EXIST IN DB*/
        $q_check_email = $connessione->prepare("
        SELECT email
        FROM users
        WHERE email = ?");
        $q_check_email->bind_param('s', $email);
        $q_check_email->execute();
        $r_check_email = $q_check_email->get_result();

        $if_check_email=mysqli_num_rows($r_check_email);

        /*IF NOT EXIST RUN QUERY*/
        if($if_check_email==0)
        {

            $q_insertcsv = $connessione->prepare("INSERT INTO users
                                        (
                                            username, 
                                            fname, 
                                            lname, 
                                            email
                                        ) 
                                        VALUES 
                                        (?, ?, ?, ?)
                                        ");
            $q_insertcsv->bind_param("ssss", $username, $name,$surname, $email);
            $q_insertcsv->execute();
            $q_insertcsv->close();


            $c = $c + 1;
            $info[] = 'CSV uploaded!';

        }

        /*ECHO AN ERROR*/
        else
        {
            $info[] = 'CSV not uploaded!';

        }
    }
}
?>

<form enctype="multipart/form-data" method="post" role="form">

    <?php echo implode( $info); ?>
    <br>
    <?php var_dump($q_insertcsv);?>

    <input type="file" name="file" id="file" size="150" required>
    <br>
    <button type="submit" class="btn btn-default" name="submit" value="submit">CARICA</button>
</form>

I don't understand what I'm doing wrong