Make sure you have the MYSQL extension turned on in the Select PHP settings and also very important step is that the PHP version you have shouldn't be rewritten by an .htaccess file, otherwise it will not work.
¿Solución?
Borrar del htaccess
<IfModule mime_module>
AddHandler application/x-httpd-alt-php72___lsphp .php .php7 .phtml
</IfModule>
