What's wrong with activating imessage information?

1, which may be a network anomaly:

Please make sure that you are connected to a cellular data or Wi-Fi network, and the network remains normal. If the network is abnormal, it is recommended to restart the wireless router or mobile phone.

2. Maybe the time zone is set incorrectly:

Incorrect time zone setting will lead to abnormal activation of imessage. Go to set the General date and time, check whether the difference is correct, and if not, please reset it.

3. This may be an application exception:

Go to Settings, then turn off iMessage and go to Settings; FaceTime call, and then close FaceTime call. Finally, restart the phone.