Frustrated Customer

Taking out the contract and having the contract was not a problem. The problem is that I decided to close the account a couple of months before my contract expired. I was given a balance to pay was told to cancel the contract and once the account is paid they will change my prepaid number from contract back to prepaid. All of that happened however 3 years later I have debt collection agencies contacting me for a balance. With this I start getting deductions from vodacom. I go to vodacom to find out what this is they advise they cant find me on the system. I speak to the collections agency MBD and I advise them to provide me with contracts and the date the account was handed over all the info for the account and they just decided to pass the account to the next debt collection agency. Im frustrated cause this is affecting my credit score negatively with no assistance. No one to help or assist