Ridiculous account

Last month I was told that I owed R13 000.00 on my phone and I had to pay so that I could get my account active again as it had been suspended. Therefore I paid this exorbitant amount. Yesterday someone from Vodacom called me and said that I owed R6000.00 and had to pay this account by the end of the month to avoid suspension again. I was told that I initially owed R17 000.00 instead of R13 000.00. So there was still R4000.00 outstanding on this account. After paying the R13000.00 last month they re activated my account and said all was paid. Now they tell me that there was R4000.00 still outstanding. I don't understand how this could be. Vodacom is a pure *******. I want to cancel my account with them and move to another network.