Truworths – Fraudulent transaction

I went to the store to buy on my account and was told the account is blocked since there is no email. I receive my statements on email so it was surprising to hear that and was given fraud contact number to call. When I called was told that there are standard bank transactions that were done and standard bank has sent a message. I told them that I didn't use standard bank for those transactions. I have only used FNB to pay and they should confirm with standard bank that I acknowledge that those payments were not done by me and they can reverse them. They Said I must go to the bank and tell them. For one I can't go to the bank and dispute transactions which are not mine. Number 2 they don't even want to give me the communication to go with to standard bank with. In my understanding they don't want to reverse the transactions and want to use me as a scapegoat. This is unacceptable. I have told them on record that they must close this account in which they refuse and say that it is on credit. I don't care about the credit they can have it. I have a heart condition and cannot be dealing with such unreasonable matters.