Change of Ownership.

So, my contract and my sisters contract was always on my moms name. We went to the store to move the contracts to our own names. So we went, took all the documents they requested, but I unfortunately forgot my payslip, which I emailed to Mimi via the help from my sister. They messed up my sisters for starters, so took them over a month to get it changed to her name, and take the payments from her. Now the problem comes with the fact that they never getting back to us with information, but they do not, we have to phone them always to keep updated. Now after we have given everything that was requested, they are now wanting other information for mine that was not required for the other contract to be moved. It also seems they have lost documents I had given them previously as they asking for them again (Like ID Etc). We did this all when it was time to upgrade. With the upgrade I was meant to get a free gift as well, which they did not have any stock of. They said they would phone when it arrived, and they haven't contacted us regarding that either. The service we have received is just terrible.