You can enable the required PHP version in panels ISPManagerhosting management. To select the required PHP version, you need to go to the WWW section -> PHP -> select (click) on the required version -> click the "As CGI" button:

Then you need to set "PHP operating mode"as "CGI" for the domain: in the WWW domains section -> select the domain -> "Change" button, select "PHP operating mode" - "CGI": You can enable the necessary PHP extensions in the PHP section -> select (click) on your CGI version -> "Extensions" button: Then you need to select the required extension and click the “Enable” button: Possible errors when changing the PHP version and enabling PHP extensions can be seen in the error log: 1. Error "Call to undefined function (PHP extension name)". To resolve the error, you need to enable the required PHP extension. 2. Error "Out of memory". To solve the error, you need to remove unnecessary/unused PHP extensions that consume RAM, or purchase additional RAM according to our instructions: How to purchase additional IP, domains, databases, space, memory?