What is the ruling on Taysir cards issued by Islamic banks with subscription fees that allow interest-free borrowing, and is the subscription fee considered interest, especially if the amount is not refunded in case of no borrowing?

The card cannot be judged without knowing its system, while paying attention to two caveats: The first is that the subscription fee might be more than the actual cost to the bank, because this increase is usury (riba). The second is that the bank might impose a penalty for late payment, and this is also usury (riba). It is necessary to ensure that every card is free from these two caveats before judging it, and not to be deceived by its source.