Warning: mysqli_connect(): (HY000/2002): Connection refused in /usr/share/nginx/html/php/class/one/ODb.php on line 21

Fatal error: Uncaught TypeError: mysqli_query(): Argument #1 ($mysql) must be of type mysqli, bool given in /usr/share/nginx/html/php/class/one/ODb.php:22 Stack trace: #0 /usr/share/nginx/html/php/class/one/ODb.php(22): mysqli_query(false, 'SET NAMES '...') #1 /usr/share/nginx/html/php/page.php(25): ODb->__construct(Array) #2 {main} thrown in /usr/share/nginx/html/php/class/one/ODb.php on line 22