Is the monitor new to you as well? If you are unable to find a software fix, you may need a hardware EDID emulator. Some monitors do not keep EDID alive when in standby, so the PC thinks they have been physically unplugged. This is more an issue with multiple monitor setups, but might cause the issue you're describing (it should come back when the monitor powers on, but I wouldn't be surprised to see icons move around, etc).
This is one example, I have no experience with this particular device, it's just the first DP version that popped up.
If you do go this route, be sure NOT to get a "headless" version. These are a different product meant for PCs with no monitor that you remote desktop into.
https://www.amazon.com/LINDY-DisplayPort-1-2-EDID-Emulator/dp/B07PF4Z58S/ref=sr_1_4?
https://www.networktechinc.com/displayport-edid-emulator.html
Displayport EDID emulator with passthrough.