Failed to connect to MySQL

Hi,
On the Visitor Statistic module : https://www.opencart.com/index.php?rout ... n_id=17612
I have error on reports when i click GO

Failed to connect to MySQL: php_network_getaddresses: getaddrinfo failed: Name or service not known
No records found.

Failed to connect to MySQL: php_network_getaddresses: getaddrinfo failed: Name or service not known

how to fix it?

The Extension is possibly unable to be used with the MySqli DB-Driver, you use,
or then, the PHP Version may play some role as well. Just a guess, I recall something
similar happen to me with some extension, a short while ago, but I had no time to check it out...
Ernie