Thank you for posting your inquiry here in Microsoft Community, torbar.
I'm sorry to hear about the display issue on your Surface. I will do my best to assist.
Try to perform the methods below:
- Force the device to restart while it's on. Press the power button for 20 seconds while the device is on.
- Run Surface Diagnostic Toolkit and check Windows Update.
- Run the System File Checker.
- Install the drivers package manually.
- Check the specific OS build of your Windows Settings> System> About.
- Download the driver and firmware for Surface, choose Surface Book 3 and click download on the next page.
- Please choose the .msi file that matches your current OS Build and click Next.
- After the download, runand installthe .msi then Restart the Surface Device
Let me know how everything goes after the steps above by replying on this thread.