1, not set in the machine communication settings;

2. The flow in the machine is loose;

3. The flow card has no flow.

Treatment method:

1. If it is a telephone line machine, check whether the telephone line is broken.

2. If it is a network cable machine, check that the network cable is not connected.

3. If it is a mobile phone, it means that there is no traffic card inserted or there is no traffic in your traffic card. Just change it.

Extended data:

Points for attention in the use of POS machines:

1. Before using the POS machine, it is necessary to check whether the power supply is connected, whether the printer and the host computer are connected normally, and whether the POS printing paper is installed.

2. At the end of business every day, the operator should perform "day-end treatment". It is particularly important to note that when the POS machine needs to be replaced for some reason, it must be turned off and replaced after the "day-end treatment" is completed.

3. Don't charge the cardholder repeatedly because of repeated swiping.

4. If you fail to swipe your card during the transaction, you need to press the required transaction code key again to avoid mistaking other transactions for "consumption" and causing repeated deductions.

Don't forget to ask the cardholder to sign the shopping list. If the cardholder's signature is inconsistent with the reserved name on the back of the card or the letter of the name on the front of the card, you can check with the issuing bank.

References:

POS machine _ Baidu Encyclopedia