Bad service

I went to upgrade my cellphone contract on the 14/05/2015 Thursday. Lwando started processing it at 15h30 and then I sign the necessary documents. After about an hour he says something is wrong with his system and he has to redo everything. I sign another set of papers. He then goes to the back and has a screaming match with his colleague. He then comes back and tells me my contract is not approved I must come back tomorrow. After I have initially told him that don't live or work around there and he assured me that it's a same day thing. He then starts screaming at me and instructs me to leave or he will call security. I tell him to cancel everything and the I left. Next morning I receive an sms saying my contact is approved. I call the store and he is day off. The lady I spoke to tells me she will process the cancellation. On Monday I go to brooklyn mtn to try and upgrade. They tell me that I have already upgraded in sunny park and I must go back there as they can't help. I called customer care who told me they will follow up and call me Tuesday afternoon. It's Wednesday and mtn call centre is not working. I can't even get hold of the store.