I got the Lacarra pos machine for no reason.

Maybe the phone number has been registered on the pos machine.

The POS machine reads the magnetic stripe information on the cardholder's bank card through the card reader, the POS machine operator inputs the transaction amount, and the cardholder inputs the personal identification information (i.e. password). The POS machine sends the information to the issuing bank system through the UnionPay center to complete the online transaction, give the information of success or failure, and print the corresponding bill. The application of POS realizes the online consumption of credit cards, debit cards and other bank cards, ensures the safety, rapidity and accuracy of transactions, avoids complicated labor such as manual blacklist inquiry and bill pressing, and improves work efficiency.