If I unplug or shut off my monitor, my usb hub setting goes back to auto detection. I have to put it back manually to usb-c before it works.
I would assume that you are using USB-C as well for video input?
What version of firmware are you in?
Hdmi 2.1 for input, firmware 106
Try setting the monitor to factory reset, then perform a power cycle (unplug, wait 10-15 seconds, then plug back in).
Try changing the setting afterwards and see if it retains it.