Side mouse buttons don't always work

I bought a new Logitech M650 mouse with programmable side buttons, opened a rainbow, put a knife on one squat on another and realized that it doesn’t work almost at all, to be more precise, with a 20% chance. I thought the problem was in the mouse buttons themselves, opened the site and no, all clicks work fine (10 clicks with each button)



In other ordinary office programs and the browser, everything is also smooth. I checked it in a couple of games and everything is okay there too. Then what's wrong with Rainbow?