Unknown number

I have been a Vodacom customer since 1998 and currently have 8 different contracts with them. Last year one of these companies that phone you and say that they are part of Vodacom and they see your number is close to expiry phoned me and said I had a number that expired a long time ago. I looked on my app and could not find the number. I then looked on my bank account and saw the deduction of R169 going off every month. Why was this not part of my normal vodacom account? I phoned Vodacom and they could not find the account on their system. I then phoned later again and they said OK they found it now. In December I told them to cancel that contract which they said they did. Now I get a call from debt service for me to pay R780 outstanding since December on this number. I cancelled the debit order this in December as my view was it was closed. Now nobody can tell me this number for the contract, I know if I am going to phone Vodacom now they will not be able to trace the number. I have now paid and they promised they will close it, but I must still call customer care to get a reference. That will be another 30-40 minutes of waiting on a line if they ever help. They are happy to take my money, but will not help me.