Warning: ini_set(): Unknown encoding "UTF-8mb4" in ini setting in /var/www/html/includes/mysql2.php on line 5

Warning: ini_set(): INI setting contains invalid encoding "UTF-8mb4" in /var/www/html/includes/mysql2.php on line 5

Fatal error: Uncaught ValueError: mb_internal_encoding(): Argument #1 ($encoding) must be a valid encoding, "UTF-8mb4" given in /var/www/html/includes/mysql2.php:6 Stack trace: #0 /var/www/html/includes/mysql2.php(6): mb_internal_encoding() #1 {main} thrown in /var/www/html/includes/mysql2.php on line 6