1: Notebook, check whether the wireless wifi is turned on. There is no general wifi shortcut Ctrl+F5.
2: If the connected network cable is connected, please check whether the connection with the computer is open. If it is on, it means it is working normally.
3. Right-click Network Neighborhood or Network Properties to see if the network is disabled.
4: Try to restart the computer.
5. See if the corridor power supply system is working normally (because corridor power supply is generally network power supply).
6. Call the telecom to provide your account number and ask whether the telecom party is in a normal state.