incorrectly debiting my account

I paid up my contract in January also cancelled it. I requested settlement amount and I was informed that I needed to pay R1808.00 of which I did. Soon after that cell c has been debiting my account with that exact amount and i contacted them and they keep on apologising without fixing this mess. Eventually they escalated it to a different department and they called me saying the matter has been resolved and to my surprise my bank accoubt had been debited again with exactly that amount. The only thing i remember about cell c as a client is a terrible experience i had with them. I regret porting my number to them. Since the day i tookbthis contraxt i dealt with people that didn't care at all. The consultant i spoke to today decided 5o hang up on me while asking for assistance