Customers cannot set the PHP version to version 7.1. Why is not this version visible for them in Plesk?
All subscriptions of these customers have the permission to change the PHP version: "PHP version and handler management" permission is enabled in Plesk > Subscriptions > example.com > Customize > Permissions.
Option I: Allow insecure under all service templates
1. Login to Plesk as administrator
2. For one exact subscription: go to Subscriptions > example.com > Customize > Permissions and enable "Set up potentially unsafe web scripting options that override the provider's policies" permission. Press OK
3. For all subscriptions of a particular service plan:
3.1. Login as Reseller with the permission problem.
3.2. go to Service Packages > package_name > Permissions > "Setting up Potentially unsafe web scripting".
3.3. press Update & Sync button
Option II: Enable CGI for version 7.1
Go to Tools & Settings > PHP Settings > 7.1.12 CGI Application and turn it on.
Option III: Remove CGI from site_isolation_settings and change to "any"
1. Login to the server over SSH
/usr/local/psa/admin/conf/site_isolation_settings.ini and set the following:
php_handler_type = any