无法获取正确的数据。 为foreach()警告提供的参数无效

The query isn;t running, not sure where Iam going wrong

Input from previous page was doctor's licence number and date from javascript calender

Posting the values using fetchApponitment function to next page->

  if(isset($_POST['BookAppointment'])) 
        { $DOCTOR_LICENSE_NO = $_POST['DOCTOR_LICENSE_NO']; 
        $APPOINTMENT_DATE = $_POST['APPOINTMENT_DATE'];

      }


        $appointmentdetails = fetchAppointments($DOCTOR_LICENSE_NO,$APPOINTMENT_DATE);
     ?>

      <table class="table-style-three">
          <thead>
            <!-- display Doctor details header  -->
            <th>DOCTOR_LICENSE_NO</th>
            <th>DOCTOR_FNAME</th>
            <th>DOCTOR_LNAME</th>
            <th>DOCTOR_EMAIL_ID</th>
            <th>DOCTOR_PHONE</th>
            <th>APPOINTMENT_DATE</th>
            <th>APPOINTMENT_TIME</th>
            <th>APPOINTMENT_STATUS</th>

          </thead>
          <tbody>
          <?php
          foreach($appointmentdetails as $displayAppointment) { ?> <!-- foreach is very important -->

          <tr>

            <td><?php print $displayAppointment['DOCTOR_LICENSE_NO']; ?></td>
            <td><?php print $displayAppointment['DOCTOR_FNAME']; ?></td>
            <td><?php print $displayAppointment['DOCTOR_LNAME']; ?></td>
            <td><?php print $displayAppointment['DOCTOR_EMAIL_ID']; ?></td>
            <td><?php print $displayAppointment['DOCTOR_PHONE']; ?></td>
            <td><?php print $displayAppointment['APPOINTMENT_DATE']; ?></td>
            <td><?php print $displayAppointment['APPOINTMENT_TIME']; ?></td>
            <td><?php print $displayAppointment['APPOINTMENT_STATUS']; ?></td>


          </tr>
          <?php } ?>
          </tbody>
      </table>

        </body>
    </html>
    <?php require_once("footer.php");?>

The function looks like this -->

function fetchAppointments($DOCTOR_LICENSE_NO,$APPOINTMENT_DATE) {
  global $mysqli,$DOCTOR_LICENSE_NO, $APPOINTMENT_DATE, $db_table_prefix,$row;
 $args = array($DOCTOR_LICENSE_NO, $APPOINTMENT_DATE);

  //echo $DOCTOR_LICENSE_NO;
  //echo $APPOINTMENT_DATE;
  echo $args[0];
  echo $args[1];
  $stmt = $mysqli->prepare(
    "SELECT doctor.DOCTOR_LICENSE_NO,
            doctor.DOCTOR_FNAME, 
            doctor.DOCTOR_LNAME, 
            doctor.DOCTOR_EMAIL_ID,
            doctor.DOCTOR_PHONE, 
        appointment.APPOINTMENT_DATE,
            appointment.APPOINTMENT_TIME,
            appointment.APPOINTMENT_STATUS
            FROM doctor INNER JOIN appointment ON (doctor.DOCTOR_LICENSE_NO = appointment.DOCTOR_LICENSE_NO) 

           WHERE doctor.DOCTOR_LICENSE_NO= ? 
          AND appointment.APPOINTMENT_DATE= ? ");           
  $stmt->bind_param("ss",$args[0], $args[1]);
  $stmt->execute();  
  $stmt->bind_result($DOCTOR_LICENSE_NO,$DOCTOR_FNAME, $DOCTOR_LNAME, $DOCTOR_EMAIL_ID, $DOCTOR_PHONE,$APPOINTMENT_DATE , $APPOINTMENT_TIME, $APPOINTMENT_STATUS);
  while ($stmt->fetch()){ 
    $row[] = array(
      'DOCTOR_LICENSE_NO'    => $DOCTOR_LICENSE_NO,
      'DOCTOR_FNAME'         => $DOCTOR_FNAME,
      'DOCTOR_LNAME'         => $DOCTOR_LNAME,
      'DOCTOR_EMAIL_ID'      => $DOCTOR_EMAIL_ID,
      'DOCTOR_PHONE'         => $DOCTOR_PHONE,
      'APPOINTMENT_DATE'     => $APPOINTMENT_DATE , 
      'APPOINTMENT_TIME'     => $APPOINTMENT_TIME, 
      'APPOINTMENT_STATUS'  =>  $APPOINTMENT_STATUS

      );
   }
  $stmt->close();
  return ($row);
 }