Warning: Undefined variable $stmt in C:\wamp64\www\MOBILE_HEALTHCARE\update_check_list.php on line 257

Fatal error: Uncaught TypeError: sqlsrv_rows_affected(): Argument #1 ($stmt) must be of type resource, null given in C:\wamp64\www\MOBILE_HEALTHCARE\update_check_list.php:257 Stack trace: #0 C:\wamp64\www\MOBILE_HEALTHCARE\update_check_list.php(257): sqlsrv_rows_affected(NULL) #1 {main} thrown in C:\wamp64\www\MOBILE_HEALTHCARE\update_check_list.php on line 257