Look at the screen of the machine that swipes your Credit card. After the card is swiped, and a transaction amount is entered, the swipe machine connects to the card’s processing centre and verifies the details acquired on swiping the card
After swiping it verifies the credit limits and approves the transaction. Once an approval process is completed, the transaction is updated to your account and the printer gets activated to print receipt.
This process is automatic for almost all swiping machines. If a print receipt is not generated after an approval, you have to assume that the transaction has been taken into your account, but perhaps the printer is faulty.
What happens if the transaction stops
If the processing of the transaction stalls on contact with the processing centre before the approval process is completed, the problem is in the reading of the magnetic tape of the credit card, and the merchant has to swipe it again. You should understand that multiple swipes before approval are harmless.
Be Alert
Always watch the process to understand how far the transaction proceeded.
Verify your statements
It is very important to Verify your account statement when you get it periodically for duplicate transactions, though it is more painful to reverse them after that stage. You can call the card’s customer care number right at the merchant establishment, ask for the last transaction detail and get the agent to confirm to the merchant that the transaction has been put through.