If your device isn't working properly, you can try several solutions to solve the problem.
In most cases you can solve the problem by following these guidelines:

If the WLAN is using a hidden SSID, you won't find the WLAN when searching for available WLANs. You can only connect to a WLAN using a hidden SSID if you know the correct SSID.

Solution: Key in SSID and security settings manually on your mobile phone.