Why is there no signal after the mobile phone card is inserted into the mobile phone?

If you use a vivo phone, if you don't recognize the SIM card, you can refer to the following methods:

1, try to restart the phone.

Please restart the phone, and the phone will re-read the SIM card to see if it can be used again.

2. Check the phone settings to see if the SIM card is enabled.

Go to mobile phone settings-mobile network-SIM card information and settings-click to enter the corresponding SIM card-enable the SIM card, and make sure the switch is turned on.

3. Check whether the SIM card is installed backwards.

Please refer to the card loading steps in the user manual to see if the SIM card is loaded in the right direction.

* Check the card loading steps: enter the settings-system management-customer service-user manual-mobile phone overview and quick start-installation and preparation.

4. Check whether the SIM card looks good.

Observe whether there are stains on the metal surface of the SIM card, and clean the stains on the surface of the SIM card to avoid the SIM card from being unrecognizable due to poor contact. If the cut SIM card is used, the shape of the SIM card may be nonstandard, resulting in poor contact and inability to identify the SIM card. I suggest you go to the operator's business hall and change to a standard SIM card.

5. Cross-validation.

Please install the SIM card on other devices, or install other SIM cards on your mobile phone for comparison test to determine whether the SIM card is faulty.

6, service center testing

If the above methods fail to solve your problem, please back up your mobile phone data in advance, take your mobile phone and purchase certificate to the vivo customer service center for testing, enter the service outlets of APP-My vivo official website /vivo Mall, or pay attention to the "vivo Customer Service"-Self-service-after-sales outlets of WeChat official account, and select provinces and cities to inquire about the service center information. It is recommended to call in advance before going to avoid idling, plan your trip reasonably and travel safely.