The Japanese version of iPhone 7 system is 10. 1. What if the call fails?

The call failed due to unstable signal. Japanese mobile phone operators are different from those in China, and there will be some problems. Among the three operators, China Unicom, China Mobile and China Telecom, Unicom's Japanese version has the best signal, but such problems occasionally occur. If you are not using Unicom now, I suggest using Unicom. Japanese mobile phones should not be upgraded and refreshed, otherwise they will be locked.

Call failure may be due to the following reasons:

This happens if the location is blind or there is no signal suddenly. It is recommended to turn the machine on and off again.

The mobile phone has poor contact, so it is recommended to change it to another mobile phone for testing.

Is the mobile phone in arrears? If the above inspection is excluded, it is still not available. Please consult the customer service to which the number belongs.

The signal transmitter is poorly contacted, dropped or flooded, or the machine is exposed to such an environment when the weather is wet.

This machine has been modified, resulting in some functional failures.