Incorrect info

Good Day. We had to replace an IPad as the previous one was damaged and had to be replaced as the old IPad we bought is no longer in existence. We purchased the IPad from the Eastgate store, and my husband went there to buy add-on for the IPad, and they could not find us on the system. Eventually they traced us via the serial number, and the contact detail on the system is not remotely close to our information. We asked them to please rectify it on the system and were very kindly informed not do-able. Should we have any issues with this IPad, we clearly are going to have a problem as it is not in our name. How do I get this rectified please as everybody at the Eastgate branch just says sorry - not their problem.