Bad service

On the 6th April I did payment at Truworths the full balance as my account was in arrears. I had asked the sales assistant what was the full balance he said R1975 which I paid in full. I received a call from MBD stating my account was not paid I told them I paid instore they should contact Truworths store. On the 16th again I did another payment on line of R1800 . I call Truworths to send me proof of payments so I can send to MBD so they can update their records. Still I have not received anything and MBD is harrassing me everyday on my phone. I need this matter resolved ASAP please