Make sure your device is physically connected to the network and/or server.

Verify that the network connection settings are entering the correct settings like SSID, IP Address, and Encryption, and that the settings are valid for the network/server.

If the network connection settings are correct, try rebooting the router, modem, and/or device itself. This can sometimes resolve temporary issues with the connection.

Look for possible sources of wi-fi signal interference or electromagnetic interference. Sources of signal interference include electronic devices like microwave ovens, cordless phones, and half-duplex hubs.