Left Bicep is Shaped Oddly

For a long time I have noticed that my left bicep is… shaped oddly compared to my right. The right bicep looks like a normal bicep with a peak, where as the left starts to peak but at the top it flattens out like a very flat plateau. Does any one have any idea if this may be genetic and just how that bicep is shaped? I have started doing some extra dumbbell reverse curls for that arm after my workouts to see if that will fix it, but so far no change. I know of high and low bicep insertion points but I have never seen this before.

Any input would be greatly appreciated at this point.

genetic. I have asymmetrical biceps too. Right one is about 16.1 inch and the other is 15.5 or so at 5’4.