Unathorised Debit Order

Last month 01 November 2017, My account was debited twice R195 x2 by Cell C, I don't have an account with Cell C and I have not taken anything from them. I went to their Shop in Fourways mall to esquire and they said i must do an affidavit. I did that and the email/fax those documents including my ID copy and they said the investigation will take 21 days than they will call me back with the feedback, fine i reversed the money but they never called me back, now today 01 December 2017 i just receive a bank notification from my bank and its another debit order from Cell C and this time they took R1648.32. Cell C why are you taking your time to investigate this matter? why is my account still being debited? Im supposed to be travelling today and I have to cancel because i wont have enough money. This is ridiculous