********ly handed over to a debt collector after paying my contract up

My contract came to it's end in November of 2021 after a 2 year period. I paid my final invoice in December and paid full. I never received a payed up / letter of close but instead got a call from MBD in February claiming that I owe R680 and some change, after getting harrased by 3-5 calls EVERY DAY and getting threatened that I will be blacklisted I gave over my account details and they took the first debit order, in the meanwhile I was trying to get a hold of Cell C's financial department but nobody was willing nor able to help. In March MBD took another R80 odd and that's when I blocked them from collecting from my account.

We are now I'm July, I was told that not only did Cell C debit me another R500 in March, but they also can't help me because it's up to MBD to give them my letter of close before they can send it to me.

I must have spent about R500 in airtime calling both companies trying to resolve the issue, I've Emailed countless times but nobody seems to have the capability of resolving the issue, or they simply don't care about ruining people's lives.

My father is going to help me start a class action against both of these companies, and if anyone would be happy to share their story please feel free to contact me.