Account settled yet balance still goes up.. how

I took out 6 months loan with the company.. paid it all in full.. debit orders went off as agreed from my account.. I called as the remaining balance was R140 paid it in minutes of receiving the settlement letter .. went as far as emailing pop.. asked for settlement letter.. and no communication.. I just logged in now and I see the balance is sitting on R280 something.. how ? How is this humanly possible as I have settled this account .. made numerous calls to a point my airtime runs out and no call back.. I need this sorted please .. someone better reach out.. I kept my end of the agreement.. please honour yours and close this account please ..