Fatal error: Uncaught TypeError: mysqli_num_rows(): Argument #1 ($result) must be of type mysqli_result, null given in /home/metvbdco/public_html/subCategory.php:23 Stack trace: #0 /home/metvbdco/public_html/subCategory.php(23): mysqli_num_rows(NULL) #1 {main} thrown in /home/metvbdco/public_html/subCategory.php on line 23