Foschini account fully paid yet problematic

I had an instore account with Foschini which I fully paid for and closed in December 2019 but I have been receiving statements saying that I owed R36 I phoned their customer care and they promised to reverse the money and close my account, following the statement said I owed R56 then the following said I owed R96 I then phoned again they told me it has been sorted I should not call again right now 13 October I received a statement saying I should pay R56 I am really exhausted now I'm tired of phoning them without any help.