Almost 2 Inch Difference Between Sitting And Standing

Hi there! So I’ve spent 10+ years on PE, mainly doing jelqing and pumping, and gained 1.5 inches in girth. I also made some length gains down the road, but the problem is they are not visible while I stand at all and I do look very short. When I sit though, I release those extra 1.2 inches and if I push the ruler I get additional 0.7 inches. Do you guys know any exercises that help decrease this insane difference? I almost have no fat, just to be clear.