I purchased a m15 at the end of February and have successfully been using both the HDMI and Thunderbolt (via USB-C to HDMI adapter) ports for a dual monitor setup. Both monitors are basic AOC 27" 60hz monitors.

Last week I got the notification that there were system updates and ran the Alienware Update program. Everything seemed to update correctly, no errors or warnings. However now my Thunderbolt port is not working. When I try to use it for a monitor the system doesn't recognize that there's a monitor attached.  

I verified that the monitor and HDMI cable were working and also bought another USB-C to HDMI adapter. Still no luck. Used the diagnostic test via Dell's support site and nothing came back wrong. I also uninstalled and reinstalled the Thunderbolt driver.  

When I hook up my phone to the Thunderbolt port, it does show that the phone is charging.

Kinda at a loss here and was hoping someone might know more troubleshooting I can do or might have some insight...