My trainer always told me to stay symmetrical never do less reps of the lesser side, even if you have to do less reps on the side that is more toned.
I used to be a pitcher, so my right side of my body was always a tad bigger due to me being right handed and doing many more reps of throwing with that arm. Takes time to get back even but you have to focus on the other side more and make sure you do the same reps as the other no matter what. Do reps according to what you can do on the weakest side, not the other. Nothing you can do quickly to fix it
probably not a helpful post