I swiped my credit card at the supermarket and four messages were sent to me.

It is possible that the banking system abnormally triggered the short message port to be sent out many times. Check the transaction details. If there is no problem, just ignore it. If you only charge it once but deduct it four times, please call the customer service number of the issuing bank on the back of the credit card immediately to report the loss of the credit card and explain the specific situation to the customer service! Then please call the police immediately.