If it is optical, (Meaning it has a laser on the bottom) You can try to unplug the mouse, Plug it in again and restart the computer. If that doesnt help, you may need to update the mouse drivers (Ask a parent or trusted adult for that!)
If it is a ball mouse, carefully have someone open the bottom of the mouse, remove the rubber marble, and clean it off as it may have some dust into it. To do this without removing the marble, we used to rub it along our denim jeans. Be careful though to not go to fast. Sometimes this can release dust that was on it. Plug it back into the computer, restart, and give it a shot!~
Sometimes a mouse may not be working correctly because it doesnt have the proper material beneith it sometimes like a mousepad. Maybe give it a shot with that or a thin book or something
