SAYING I OWE MONEY WHEN I DON'T!!!!

I signed a vodacom contract with Autopage for a Laptop many years ago, after falling behind in payments I contacted them multiple times to receive a quotation via email to settle my outstanding account.

After THEM failing to send me an invoice I get contacted by a Debt collection agency on behalf of Vodacom to settle the account, fine. I make the monthly payments and the account is settled in a few months.

Now almost 3 years later, I get contacted by another collection agency on behalf of Vodacom requesting R5000 outstanding.

This is absolutely the worst company in South Africa and I have no idea why they are still active.

Even on my monthly credit report it says my Vodacom account is not in areas and was closed!!!

What are they trying to do, **** me out of money??!!