Is your Windows set to put the monitor to sleep after x amount time? I've had an issue on my previous monitor where the monitor even though I manually turn it off on the button, won't properly wake up or weird out when tapping the keyboard r moving the mouse to wake the display up (my PC also stays on overnight but is never set to auto sleep, just sometimes the display was set to sleep after 30 mins idle).
Turning the feature in Windows off to never put the monitor to sleep fixed that. The same thing happens on the QD-OLED so it's a Windows bug when combined with certain GFX cards and drivers by the looks of it where sometimes the display won't wake when the OS puts it to sleep, or will do funky stuff when waking up.
Ever since I have just used a black screen screen saver instead so the panel itself isn't actively "on" since it's OLED, and then manually turn the monitor off as and when needed.