******** deduction

At the end off April MTN deducted R1812 from my account, which is a 2GB contract with a R1 credit limit. Went to Karaglen Mtn store to report it and Siphiwe was very helpful although it seems that there is also only so much that he can do! I reversed the transaction at the bank and now I get messages that they are going to suspend my account if I don't pay. I asked for a detailed account showing that I used that, but without any luck. The long and the short is that I've got an account that can not go over 2GB, but according to them, it did. Went to Rivonia branch today, because I was referred there, came there, and it was closed due to the strike! What to do and where to go??