What is the reason why Unicom card has no service?

If you use a vivo phone, you can refer to the following methods for troubleshooting:

1. It is recommended to check whether metal protective shell, magnetic protective shell, magnetic bracket and other accessories are used. Metal and magnetic materials easily interfere with signal reception. It is recommended to remove the fittings for inspection.

2. If you are in a closed indoor environment (such as basement, elevator, etc.). ), the cell phone signal may be blocked, resulting in poor signal, you can go to the outdoor environment to check. If you are in a remote area, the signal may be poor, so you can use the cell phone signal of the same operator network around you to determine whether it is the cause of network coverage. ?

3. Observe whether there is dirt or oxidation on the metal surface of the SIM card, and check it after cleaning. If you use a tailored SIM card, it is recommended to replace it with a standard SIM card, install the SIM card on other devices, or install other SIM cards on your own mobile phone for comparative testing to determine whether the SIM card is faulty. If it is due to the SIM card, it is recommended to go to the operator's business hall to make up the card.

4. You can go to Settings-System Management-Backup and Reset-Reset the network settings (select the corresponding SIM card)-Reset the settings before viewing (Resetting the network settings will delete and disconnect the connection and pairing records of WLAN, mobile data network, Bluetooth and other networks. Before operation, it is recommended to back up data such as WiFi account number and password, and you can enter mobile cloud service-device cloud backup-backup data type-open system data. ;

5. Check whether it is the latest version (some models are being set up-system upgrade) in the phone settings-My device -ikofun Touch OS/Monster/UI interface. If a new version of the push notification is detected, it is recommended to update to the latest version in time.

6. Enter Settings-More Settings/System Management-Restore Factory Settings/Backup Reset-Try to restore all settings (it is recommended to back up important data such as contacts, information and pictures in the mobile phone first, cancel the account of vivo and third-party software, and programs such as WeChat may need to log in again);

If the above operations are not solved, it is recommended to take the mobile phone to the official customer service center of vivo for inspection. The address and contact information of the service center can be found in official website-the outlets serving vivo-click to view all-select your province and city-and check the local customer service center.