xprofile_get_field_data is getting empty string from "date" field when used in "profile_update" hook

[newjie]

 add_action('profile_update',function($user_id,$oldData,$newData){
   require_once('updateUsersToSheet.php');
   updateUsersToSheet($api_url,$user_id);
 },10,3);

I am using the above code to send user data to a google sheet when the profile is updated. I have a "date" field which allows user to choose their birthday, and its field_id is 33.
In updateUsersToSheet.php，if I do
var_dump(xprofile_get_field_data(33,$user_id));

It will output an empty string. However, if I put
var_dump(xprofile_get_field_data(33,$user_id)); in function.php, it will correctly output the users' birthday.

I also tried to get this data from custom api

// get User bDay
add_action( 'rest_api_init', 'returnUserBday' );
function returnUserBday(){
  register_rest_route( 'wsk/v1', '/userBday/', array(
      'methods' => 'GET',
      'callback' => 'getUserBday',
  ) );
}
function getUserBday( $request ) {
  $id = $request->get_param('id');
  $bday = xprofile_get_field_data(33,$id);

  $response = array(
      'bday' => $bday
  );
  return rest_ensure_response( $response );
}

It also outputs an empty string.

I have tried create another "html5 date picker" field, and it doesn't have this problem.