Did the WAN port get the IP?

2. If the WAN port can't get IP, please plug the network cable directly into the cat broadband dial-up to see if it can be dialed.

If you can't dial the cat directly, please contact your ISP.

If the direct cat can dial, only the router can't dial.

Then it is generally a router hardware failure.

4: I can get on WIFI, but suddenly I can't get on it.

Then it has something to do with the router cache. Users are advised to dial the power cord behind the router and plug it in again. When the signal indicator lights up again, the phone will try to connect again.