Swindling Edcon

My mom is 81 years old, so i am writing this while she sits next to me. She doesn't know how to operate a computer. Edcon has been deducing R97,50 *******ly every month since she opened her account few years ago. This money goes towards a hospital plan she was told she is too old to belong to when she opened up the account. Even their instore personnel have contacted head office to get them to stop deducting. But every month it is being deducted. she stopped paying as according to us she must have a build up of a large amount of money now due to this R97,50 that never gets credited against her account and then they event charge interest. She refuses to pay any further until the money has been credited against her account, This is now going on for years! It is atrocious and then their collection agency borders on harassment and still nothing happens. Is this how Edcon makes their money? ******** old women?? How can she pay for something she does not qualify for?? She has been paying R600 a month for a year without buying anything and the balance due remains the same. How on earth do this maths work?