Have you tried changing your mouse like I said. I only saw you start shooting over the guys head, then you wen right in on his chest and there was no hit marker. If you are seeing a hit marker, it means you hit the guy. If you think you are not hitting him consecutive, in other words if you dsidn't let go of the button, then a shot didn't register. Then I stand by what I said. Buy a new mouse and see if you still have issues. Change your debounce setting. there is online websites too you can check for double clicking, but they are not that reliable. You might not every be able to reproduce it until you check with a new mouse. As was the case with me in the past brother on other games. LIke I said, I noticed it in online chess in a browser, but not when I played bfv for example lmao. And honestly I only changed my mouse, just for the hell of it, first I changed to another olds mouse, that also had a bad button which I never realized. Finally bought a whole new mouse brother. And then all of sudden the issue I had playing chess was gone. I also have an ibuy power mouse right now, that has a terrible click consistency and its brand new lol. I ended up purchasing an mchose l7 Pro +, and its like godmode brother. Actually if you can find the l7 Ultra without the plus get that one. it has the newer sensor.
Brother, I have like 6 mice right now. All with bad left buttons, but you would never be able to tell anything is wrong with them. mice need changing frequently because of this issue at least with me.