Absa credit loan

Hi am here about something bad or bad service at Absa Richards Bay. My mother took a credit card with them and the problem is she has been paying but the balance she owes doesn't decrease if she goes to the bank about these with bank statements to prove that the money its being taken monthly for credit card payment but the balance doesn't go down she says that they do even look at those bank statements they only say she is paying small amount mind you she is paying the amount they agree on so i dont know whats really going on there and i wish to get answers...because these thing is stressing my mom now she is unemployed now but she makes sure that they do get their cash of which it seems to disappear in to thin air.