Symptom:
Issue in service parameter page on subscriber node.

Conditions:
Go to system-service parameter-select subscriber- any services

Change some values then save it.status is update successful.

Once again click on save, it shows existing data with update successful status.
This issue is there in all services.

If save is happening properly then move to other service,  check there then return to the previous service.

Sometimes it is not ready to take new value.

For only few services  ,POP UP tells to restart the service in serviceability page to take effect . 

But in publisher side they are working properly.

This issue plays big role on "Clusterwide Parameters (Parameters that apply to all servers)" .

Do some modification in subscriber under clusterwide parameter then compare edited value in publisher and subscriber.