First, if using a home network, it is recommended to connect to other wifi or mobile phone personal hotspot for testing and checking:
If the connection to other WiFi is normal
(1) Please do not stay away from the router;
(2) Please check whether the broadband account expires, restart the router and restart the phone before trying;
(3) If the router has been set to blacklist or whitelist, check whether the mac address of the mobile phone is added to the router. If the router is not set to blacklist or whitelist, please power off the router and restart it.
Reason analysis; In this case, it is because your wireless network has a problem, so the mobile phone can not connect to the network, and the broadband battery is a cable network problem.
Or maybe it's your phone