When login the P-series PBX with the user, there is no Import/Export button on the extension page, so you can't import and export the extensions.
Yeastar P-series PBX
This is our design. For safety and to make the system stable, it only allowed the admin can import and export the extensions. Login to the P-series PBX with admin and you will find the button.
Note: It will not work when login in with a user and the user role is administrator, please login with the admin account.