I had the same thing happen recently, and came across this Youtube video detailing a fix: https://www.youtube.com/watch?v=yFaLyoSQQo0 https://www.youtube.com/wa

I had the same thing happen recently, and came across this Youtube video detailing a fix: https://www.youtube.com/watch?v=yFaLyoSQQo0 https://www.youtube.com/watch?v=yFaLyoSQQo0. Essentially, you open up the mouse and loosen the internal screws on the thumb button a little bit, which moves the board away from the rubber over the button and relieves whatever pressure is keeping it pressed. You need a screwdriver with a T5 Torx bit to open up some of the screws, but overall the procedure is pretty easy and my mouse has been working great ever since.