我在我的foreach循环下有我的更新声明，我在其中尝试更新成员状态，并且有一个用于更新的按钮。但是我一直试图找出我在哪里弄错了，因为它确实显示了任何错误，但是仍然没有更新。你能帮忙吗？

foreach( $results as $user_data) {


        $startTimeStamp = strtotime($user_data->deposit_date);
        $endTimeStamp = strtotime($current_date);

        $timeDiff = abs($endTimeStamp - $startTimeStamp);

        $numberDays = $timeDiff/86400;  // 86400 seconds in one day

        // and you might want to convert to integer
        $numberDays = intval($numberDays);

       $roi = $user_data->amount * 2;  
       $amount_growth = $roi - $user_data->amount;


     $output .= "<tr>
    <td> $user_data->ID</td>
    <td> R$user_data->amount</td>
    <td> $user_data->deposit_date</td>
    <td> $numberDays</td>
    <td> R$amount_growth</td>
    <td> R$roi</td>
    <td> <form method='post'> <input type='submit' name='submit' value='Confirm Deposit' /> </form> </td>

  </tr>";

     //Add Withdrawal
     if($_POST['submit']) {

      global $wpdb;
      $table_name  = $wpdb->prefix."member_deposit";

      $todate = date('Y-m-d H:i:s');   


        //Update Member Status
        $status = "Yes";
        $where = array('ID' => $user_data->ID);
            $subs = array('conf_deposit' => $status);


       $success = $wpdb->update($table_name,$subs,$where);