PHP and MYSQLI Issue (Im learning)

Question

I'm writing a page to work as a forgotten password which emails a link with a token, for the most it works perfectly and up until line 89 which is to update the user table with the token and exp date for the token, I get nothing, no errors no success, it doesn't even return me to the index.php page defined on success

Line 89 is just after the commented-out section which emails the user, up till this point all works perfectly

I'm learning as I'm building, to be honest, so I have no formal training I have used the mysqli_prepare statements on the Register and Login pages but there is a select and insert statement this is the first time with an UPDATE.

From my existing pages and web guides/references, I can not see where I have gone wrong.

Any help you can give would be much appreciated.

    <?php
// Initialize the session
session_start();
 
// Check if the user is logged in, otherwise redirect to login page
if($_SESSION["loggedin"] == true){
    header("location: password-change.php");
    exit;
}
 
// Include config file
require_once "inc/config.php";
 
// Define variables and initialize with empty values
$email = $human = "";
$email_err = $human_err = "";
 
// Processing form data when form is submitted
if($_SERVER["REQUEST_METHOD"] == "POST"){
 
    // Validate email
    if(empty(trim($_POST["email"]))){
        $email_err = "Please enter a email.";
    } elseif(!preg_match('/^([a-zA-Z0-9\+_\-]+)(\.[a-zA-Z0-9\+_\-]+)*@([a-zA-Z0-9\-]+\.)+[a-zA-Z]{2,6}$/', trim($_POST["email"]))){ 
        $email_err = "email can only contain letters, numbers, and underscores.";
    } else{
        // Prepare a select statement
        $sql = "SELECT id FROM users WHERE email = ?";
        
        if($stmt = mysqli_prepare($link, $sql)){
            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "s", $param_email);
            
            // Set parameters
            $param_email = trim($_POST["email"]);
            
            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){
                /* store result */
                mysqli_stmt_store_result($stmt);
                
                if(mysqli_stmt_num_rows($stmt) == 1){
                    $email = trim($_POST["email"]);
                } else{
                    $email_err = "No email like this exists.";
                }
            } else{
                echo "Oops! Looks like Something went wrong. Please try again later.";
            }

            // Close statement
            mysqli_stmt_close($stmt);
        }
    }
    
    // Validate human name
    if(empty(trim($_POST["human"]))){
        $human_err = "Please enter your answer (In Numbers)"; 
    } elseif(!preg_match('/[0-9]$/', trim($_POST["human"]))){ 
        $human_err = "Your answer can only contain numbers."; 
    } elseif(trim($_POST["human"]) != 12 ) { 
        $human_err = "Sorry thats incorrect, please try again."; 
    } else {
    }
 
   // Check input errors before inserting in database
   if(empty($email_err) && empty($human_err)){
        $token = md5($email).rand(10,9999);
        $expFormat = mktime(date("H"), date("i"), date("s"), date("m") ,date("d")+1, date("Y"));
        $expDate = date("Y-m-d H:i:s",$expFormat); 
        $link = "<a href='https://www.heroestable.com.au/reset-password.php?key=" . $email . "&token=" . $token . "'>Click To Reset password</a>";

        //  $toMail = "peddlerstable@gmail.com";
        //  $header = "From: Trevor <trevormulley@outlook.com>\r\n" .
        //  "Content-Type: text/html; charset=UTF-8\r\n" .
        //  "Reply-To: trevormulley@outlook.com\r\n" .
        //  "X-Mailer: PHP/" . phpversion();
        //  $MySubject = "User password request request from [HeroesTable.com.au]\r\n";

        //  $body = "<p>Hey there friend,</p>" .
        //  "Someone has requested the password to be reset for this email address: $email.<br>" . 
        //  "If this wasnt you please ignore this email as no change has been made, otherwise please click the link below to reset your password." .
        //  "<p> $link </p>" .
        //  "Regards<br>" .
        //  " - Trev<br><br>" .
        //  "<img src='https://heroestable.com.au/images/heroes-table-disc-150x150.webp' width='150' height='150'>";
        //  mail($toMail, $MySubject, $body, $header); 

    // Prepare an update statement
    $sql = "UPDATE users SET reset_link_token = ?, exp_date = ? WHERE email = ?";
    
    if($stmt = mysqli_prepare($link, $sql)){
        mysqli_stmt_bind_param($stmt, "sss", $param_token, $param_expDate, $param_email);
        // Set parameters
        $param_token = $token;
        $param_expDate = $expDate;
        $param_email = $email;

    // Attempt to execute the prepared statement
    if(mysqli_stmt_execute($stmt)){
        header("location: index.php");
        exit();
    } else{
        echo "Oops! Something went wrong. Please try again later.";
        echo("Error description: " . $stmt -> error);
        echo "<br>"; print_r($_POST);
    }

    // Close statement
    mysqli_stmt_close($stmt);
    }
    }
    
    // Close connection
    mysqli_close($link);
}
include "inc/headder.php"
?>

<body>
<div class="center padd-text-top">
  <div class="auth">
    <h2>Forgot password</h2>
    <p>Please enter your registered email address and the human check and we will email you a link to reset your password.</p>
    <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post"> 
        <div class="form-group">
            <label>&nbsp;</label>
            <input type="text" name="email" placeholder="email address" class="form-control <?php echo (!empty($email_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $email; ?>">
            <span class="invalid-feedback"><?php echo $email_err; ?></span>
        </div>
        <div class="form-group">
            <label>&nbsp;</label>
            <input type="text" name="human" placeholder="What is six plus six? (Numbers Only)" class="form-control <?php echo (!empty($human_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $human; ?>">
            <span class="invalid-feedback"><?php echo $human_err; ?></span>
        </div>
        <div class="form-group">
                &nbsp;
            </div>        
        <div class="form-group">
            <input type="submit" class="btn btn-primary" value="Submit">
            <a class="btn btn-link ml-2" href="index.php">Cancel</a>
        </div>
    </form>
  </div>    
</div>
  </body>
</html>