therealalexander just to confirm, your device cannot locate your Modem/Router's SSID? If that is the case, it might have been accidentally disabled by someone. In order to fix this, you may need to connect your computer directly to the modem using an ethernet cable, Once you're connected, go to your modem's UI by opening a browser and going to 192.168.254.254. From there, you'll be prompted to login. I believe that the installer left you the credentials to login to your modem (it's different from your SSID and Modem Passcode)? And from there you have to go to the different settings to check if WLAN is enabled.
I hope this helps.