Please install mysqli into your centos server .
To install mysqli using EachApache:
- Login to WHM as 'root' user.
- Either search for "EasyApache" or go to Software > EasyApache
- Scroll down and select a build option (Previously Saved Config)
- Click Start "Start customizing based on profile"
- Select the version of Apache and click "Next Step".
- Select the version of PHP and click "Next Step".
- Choose additional options within the "Short Options List"
- Select "Exhaustive Options List" and look for "MySQL Improved extension"
- Click "Save and Build"