Termination of Cellphone number whithout notification

My cell phone number was terminated by cell c without them even notifying me that they will terminate my number, I have been using this number for more than 7 years and all my OTP's go to this number, I am told that it is permanently cancelled due to my account being over 120 days old funny enough cell c was able to debit me on 28th December my question is why did they not debit the full amount owed? I have been trying to get the account re-activated and no one seams to know what's going on, I spoke to one of the supervisors to send me all the details plus banking details and the amount owing but all he sent is the amount owing and ref number, I need someone who will ensure that my number is restored once payment is made and also take the debit order that was made on 28 December into account.