A day before, I found that my screen was yellow. I found that 'Night light' was turned on in Windows 10. Today, at the same time, it happened again. I am pretty sure that there is no schedule set for Night light. What might be the problem?
Double check 'Night light' is set to off:
Then make sure 'Schedule night light' in 'Night light settings' is also set to off:
If 'Night light' is always turning on at the same time every day, then it is most likely that 'Night light' schedule is active, and this step should resolve the problem.
If this doesn't work, then you can always just set your 'Night light' strength to zero.