Why doesn't hair fall out from upper lip after laser hair removal treatment?

Hi! I had a 8 laser hair removal treatments on my upper lip but hair is not falling out at all. Laser Soprano ICE (Alma). Skin type- white. Hair-dark. My skin is quite dry. I had a laser hair removal procedure on my bikini and legs- it worked perfect. I was thinking that maybe something is wrong with hormones but tests were OK. What could be the reason why hair is not falling out from my upper lip? Could it be that I am not moisturizing my skin good enough? Thank you.