Multichoice
What is the correct procedure?

I've sold my PVR to another person and now I transfer it to him. So I'm (Seller) told to phone in with all the details of the Buyer to initiate the transfer. I got the details and phoned in again only to be told that the Buyer needs to phone in with my (Seller) details.

So which is it now? What needs to be done? What are the correct procedures of transferring a decoder?