Unable to install Roundcube missing mysqli module

Help! (Home for newbies)
1

Hi I’m new to this control panel, I want to install Roundcube, when I use the Install scripts and select Roundcube 1.3.8 - I get the following message:

PHP module mysqli is required …
… could not find domain’s php.ini file

I’ve researched and added the following line to the installed PHP 5, 7, and 7.1 ini files:

extension=mysqli.so

Rebooted VPS server

But still same problem, can anyone help…? Much abliged

2

Do dpkg --get-selections | grep “mysql” If php(version)-mysql is not on list or in wrong php version install the missing one with
sudo apt-get install php5-mysql or sudo apt-get install php7-mysql