Thunderbolt issues on Dell XPS 15 9510 and Ubuntu 18.04

Hello. I have a new Dell XPS 9510 laptop that is having issues with thunderbolt connectivity on Ubuntu 18.04.

I have tried BIOS versions 1.2 and 1.4 as well as adjusted thunderbolt settings within the BIOS but still nothing works.

I can use the thunderbolt ports for USB drives but connecting to external monitors doesn't work. Also, in the thunderbolt settings in Ubuntu it says that nothing is detected.

Would appreciate some support to fixing this. Thanks!