The network cannot be connected, error 651, it is diagnosed that there is no ip configuration, how to solve it

The network cannot be connected, error 651, it is diagnosed that there is no ip configuration, how to solve it.

 
Error code 651 appears, it is recommended to troubleshoot from the following aspects:
1. Restart the optical modem and plug in the optical fiber connector;
2. Judge whether the status of the light modem is normal, if it is abnormal (the light modem is red/PON light flashes/the indicator light is abnormal), you can call the local 10086 for broadband fault reporting;
3. Remove the router and directly connect to the optical modem dial-up connection to surf the Internet. If the dial-up connection fails, you can use the broadband fault reporting center for further feedback and processing;
4. Reconfigure the router.