There is no need to deduct any handling fee for credit card refund. For example, we usually go to the hotel to check in, and the advance payment is also swiped, and it will be swiped again when the room rate is settled. All the money goes back to the credit card except the room charge, and no handling fee is deducted.

The landlord may have found a problem with the water heater you bought with your credit card and asked the mall to return it, but the refund from the mall didn't reach your card, and at this time your repayment period just passed, resulting in interest.

However, it is impossible to deduct the interest on buying a water heater 170 yuan. Call the credit card center for details before going to Suning.