******* Debit order of R26 972.55!!

Long story short, I tried to take out a cell phone account from MTN direct. They didn't tell me the phone wasn't in stock and after many phone calls after a whole month I sent hadn't received the phone delivery... Therefore I had not signed anything... After an entire month of patience I told them to cancel the contract as the situation is actually in believable... Despite not signing anything and requesting for the cancellation there was still 2 months debited. Despite the incredible inconvenience of being transferred from person to person telephonically they have now proceeded to debit R26 972.55 out of my account. Please tell me HOW is this legal???? And of course now any legitimate debit orders that need to come off between this evening and Monday when I can get to the bank, cannot be paid for!!!! Mtn Direct is impossible to deal with, obviously ***********, has caused a GREAT DEAL of inconvenience in my life over the past 4 months.