Attaching an external keyboard for testing and identifying hardware issue.  If the laptop is under warranty, click on Get Help Now button on lower right of this screen.

Had a play this morning, I've plugged the laptop into my hub so I can use the monitors and for some reason the F keys are now working.

After some testing, it seems that, if I start the laptop already plugged into the hub, then later disconnect it and use it on its own the F keys stop working. Plug it back into the Hub and they start working again.

strange.

Glad to hear that it got resolved.

For anyone else facing this issue:

This issue resolved for me by doing the following:

1. Shutdown the laptop.

2. Click the power button

3. When XPS shows on the screen click the F12 key. (If this is not showing for you, you'll need an external keyboard)

Please note - This can be difficult and F12 needs to be pressed at the exact right time. For me it was about 5 seconds after the XPS logo appears. You may need to shutdown and try again multiple times. If all goes well you will see a 'One time boot settings' screen appear.

4. Under Pre-Boot Tasks > Click the BIOS Flash Update - Remote option (Ensure you are plugged into ethernet, I am not sure if you can do this on Wi-Fi).

Once the BIOS update is complete it began working for me. I did try a BIOS update previously via the dell command software but the only way the BIOS update truly worked was this method.

Hope this helps someone!