What exercises do you do? Impingement is usually due to underdeveloped rotator cuffs. Doing some max strength training (with dumbells, not just rubber bands!) should help with that (if you don’t have a tear of course). Great exercises are internal and external rotator cuff rotations, but careful not to overdo yourself, especially if you have a tear or inflammation. I wouldn’t advise too much resting since the muscles will weaken and it’ll just get worse.
I have quite some imbalances myself, but whenever I do such a workout my shoulders always feels relieved and stronger.