MBD - Settle account

Made an agreement with MBD after receiving a SMS qualifying for a discount. 3 months later, the account should have been paid off as agreed! Now we're being told that we still owe 3500??? Received a statement which shows a bbf (as of Dec) of R8000 odd, paid 4000 odd in Dec and another R4000 (BALANCE) in Jan, WHICH CLEARLY SHOWS THE ACCOUNT HAS BEEN PAID. How can a statement with payments made not correspond with what your call agents are saying!

Now we're trying to get answers but their agents are giving us the run around! From late collections, to ASC to the call centre and finally customer care, which I may add doesn't pick up the phone and cuts off after 4mins!