Display -> Display Resolution doesn't stick in Windows 10 between reboots

Hello:
I have a MBP 16" which I use with an old Thunderbolt display. I use the laptop screen & the external display at the same time.
The graphics resolution setting is set to Best for external displays.
The problem that I have is that I have the Scale and layout set to 100% (this sticks) but the Display Resolution always gets reset after I reboot the VM to 3584x2240.
I like to set it to 1680x1050. I am kind of getting annoyed having to to set the display resolution every time I start the VM.
Any ideas why windows doesn't preserve this setting? Is it enforced upon it by the parallels configuration?

Thanks!