Logitech G 602 Mouse question

In the past when I would press my wheel a black mark would appear on my page and if my cursor went below that mark the page would scroll down. If my cursor went above that mark , the opposite would happen. I don't know what changed it, but now I have to manually move the wheel with my finger to scroll the page.
In easy to follow directions how can I fix it ?

Do you have the basic mouse driver installed or a logitech one? You would need the logitech driver installed to have that capability.

I installed the driver then made the wheel 'generic' now it works , thank you.