Mouse scroll wheel works but goes in both directions

Mouse KM7321W. The mouse wheel will scroll down 3 lines and then scroll upwards 2 - 3 lines. The scroll wheel wasn't working properly.

The solution is to put W40 on the metal joint that is perpendicular to the wheel.

Here is a video that shows how to open the mouse and where to apply the W40. The inside of the mouse in the video is very similar to my mouse.

I only applied it to the wheel joint and moved the scroll wheel according to the video. It worked immediately. I didn't need to separate the wheel from the plastic holder and add W40 to the 2 buttons under the wheel.

https://www.youtube.com/watch?v=gnZhGLzOasc [youtube.com]  Start from 1 minute of the video.