The person who signed the contract with the phone company, i.e., subscriber, with the identity document, must reach a node and there to make a statement. If the customer care Department will go to someone else, then it must be a notarized power of attorney from the owner with the right to disconnect and connect services.
The exact wording how to write a statement on the shutdown of eight, you point to the place, but it is enough to write: "Please disable long distance/international calls on their own. Number. Signature.
Disable eight on the phone is considered a modification of the tariff, and this service is chargeable. It is inexpensive, but still have to fork out.
Service outage of eight made 3 working days