The mountain clip alarm has an annual fee and a telephone bill. Why can't it be used?

1. The mobile phone card is in arrears; 2. The alarm has no electricity; 3. The signal is not good; 4. The alarm is damaged.

Solution: 1. It is recommended to press and hold the power button for 1 seconds, then turn it off and then turn it on again. 2. Whether you can enter Recovery. How to enter Recovery: In the shutdown state, press and hold the "Volume Increase Key" first, then press and hold the "Shutdown Key", and then let go when the boot screen appears to enter Recovery. If you can enter Recovery, please switch the system and back up the data under Recovery. If you can't succeed, you need to clear all the data (address book, SMS, mobile phone applications, etc. will disappear). 3. If the problem remains, it is recommended to brush the firmware again.