Continuously? Never stops? Up and Down?
Only Down?
Only Up?
Only down and when it gets to the bottom it stops?
Does the position of your mouse cursor seem to influence the behavior one way or the other?
Typically scrolling behavior is controlled by one or both of your commonly 2 (two) input devices, so....
That's where I'd start (looking for stuck keys) keyboard common navigation keys (arrows, page up, home, end, etc.)
Mouse scroll wheel
Both keyboard and mouse batteries if applicable.
We had an issue back in Windows 10, where if you had a desktop background setup as a slideshow and (as I recall) you also had the box labeled Automatically pick an accent color from my background (under "Colors") ticked, then that would often result in File Explorer windows that were open to randomly scroll about.
No way of knowing if that weird condition has reared its' ugly head again.