Hope you are talking about unsubscribing the phone from IPMA service and you can do it from phone, go to top right corner of device level, select 'subscribe/unsubscribe services' you will find there the list of services the phone has been subscribed so far, you can unsubscribe/subscribe any phone service from here.
If you don't need the service systemwide, just delete the service from 'Phone Services' page.
HTH.
