Before deleting an SMS gateway, you must disassociate the gateway from all the Policy Servers. See Disassociating an SMS Gateway from all Policy Servers.
Deleting an SMS gateway definition removes it from the list of gateways that a Policy Management device can use to send SMS messages. To delete an SMS gateway definition, delete it from the ALL group. Deleting a network element from the ALL group also deletes it from every group with which it is associated.
To delete an SMS gateway: