Why did 12 send a message and receive it at 4 o'clock?

The message sent at 12 was received at 4 o'clock because there was no network signal on the mobile phone, and the mobile phone program failed after starting, as follows:

1, there is no network signal on the mobile phone: if you don't turn on the network during this period, you can't receive information.

2. The mobile phone program has failed since it was started: it directly leads to the inability to send information. You need to check whether WeChat is in the mobile phone's self-startup. If not, the background system of the mobile phone will automatically turn off the startup of most software on the mobile phone and close the program, so you can't receive information until you use this program again.