Fatal error: Uncaught TypeError: set_error_handler(): Argument #1 ($callback) must be a valid callback or null, function "error_handler" not found or invalid function name in /usr/www/toxicdocter/public/index.php:69 Stack trace: #0 /usr/www/toxicdocter/public/index.php(69): set_error_handler() #1 {main} thrown in /usr/www/toxicdocter/public/index.php on line 69