MWEB is steeling

In December i asked for my line to be moved from one house to another, all in the same complex, it took so long that I asked for my service to be canceled, this was in December, then the call centre person told me that there will be a penalty for cancellation before end of contract, I was so happy to pay the penalty because the service was so bad. I paid the cancellation penalty end of January and I thought all is well. Then at the end of February MWEB tries to take the same amount as the cancellation fee that I already paid. Which means that MWEB is trying to steel my money. Now i get emails stating that my account is behind and that I must pay the outstanding amounts. The service was so bad that I actually paid money for the service to be canceled, why would I try to keep my service going with MWEB????