function mailit()
    {
            $rand=rand(100000,999999);
            $user=$_SESSION['user'];

            $sql=mysqli_query($db,"UPDATE `patient_login` SET `otp`='$rand' WHERE `patient_id`='1'");

            $mail = new PHPMailer;

            $mail->isSMTP();                                      // Set mailer to use SMTP
            $mail->Host = '';  // Specify main and backup SMTP servers
            $mail->SMTPAuth = true;                               // Enable SMTP authentication
            $mail->Username = 'myusername ';                 // SMTP username
            $mail->Password = 'mypassword';                           // SMTP password
            $mail->SMTPSecure = 'tls';                            // Enable TLS encryption, `ssl` also accepted
            $mail->Port = 587 ;                                    // TCP port to connect to

            $mail->setFrom('dont_reply_back@example.xyz');
            $mail->addAddress('$row');     // Add a recipient
            $mail->addReplyTo('dont_reply_back@example.xyz');


            $mail->isHTML(true);                                  // Set email format to HTML
            $mail->Subject = 'THis is your OTP';
            $mail->Body    = 'Your otp is '.$rand;

            $mail->AltBody = 'This is the body in plain text for non-HTML mail clients';

            if(!$mail->send()) {
                echo 'Message could not be sent.';
                echo 'Mailer Error: ' . $mail->ErrorInfo;
    }
  }

$mailadd=mysqli_query($db,"SELECT `doctor_email` FROM `doctor_login` WHERE `doctor_id`='1'");
    $row = mysqli_fetch_array($mailadd,MYSQLI_ASSOC);
    echo $row['doctor_email'];
    $row2=$rowa['doctor_email'];
    echo $row2;