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Fatal error: Uncaught TypeError: mysqli_query(): Argument #1 ($mysql) must be of type mysqli, null given in E:\SHS\xampp\htdocs\guidelines.php:17 Stack trace: #0 E:\SHS\xampp\htdocs\guidelines.php(17): mysqli_query(NULL, 'select * from f...') #1 {main} thrown in E:\SHS\xampp\htdocs\guidelines.php on line 17