Vodacom unable to change my surname!

I have had it with the terrible service from Vodacom. I was recently married and tried changing my surname with Vodacom four times now. The first two times I went to stores (Caledon where I upgraded my contract and Durbanville) and the consultants told me they changed it on the system. My name stayed the same on all my statements etc. though. I went to the store once again over the weekend only to be told that they can't change it in store and that I need to phone ********** . Phoned it this morning and the lady told me that they can't change it as her system does not allow this and that I need to go to a store!!!!!!!!!!!!!! How ridiculous is this? How can Vodacom not know how to change my details? The lady then told me to go to the store and if they can't change it in the store, the consultant needs to phone Vodacom from the store to change it! I have three contracts with Vodacom which luckily all come to and end during this year.