Why can’t I use the China Radio and Television mobile phone card?

1. The mobile phone SIM card has poor contact with the mobile phone card slot shrapnel, causing the SIM card circuit to fail to work and the mobile phone to be unable to communicate with the network base station. At this time, you can take out the SIM card, wipe the gold finger of the SIM card with a clean cotton cloth, and then reinstall it. 2. The system software turns off the modem in the signal processing circuit of the mobile phone because the installed application software is incompatible with the system. At this time, the mobile phone can be shut down and restarted, and the modem in the mobile phone signal circuit will restart. After the signal is normal, suspicious mobile applications installed before the problem occurred will be deleted. 3. The SIM card of the mobile phone is not registered in the network. At this time you can insert this SIM card into another mobile phone. If it also shows that there is no service, it is the SIM card. 4. Due to unexpected reasons, the mobile phone SIM card failed to reconnect to the search network after there was no signal in the network signal coverage area. At this time, you can manually search for network registration again under the menu of Settings-General-Network-Network Operator. 5. The reason is that the signal coverage of the mobile phone SIM card network operator is insufficient. At this time, you can change the location to an open area and then check the display of the mobile phone signal grid. If the display is normal after changing the location, you can call the service hotline of the network operator for feedback and complaints. 6. The phone card has been used for too long. You can go to the local business office to apply for a new card with a valid ID. Hope this helps!