apple watch created a dent in my wrist

I have been wearing apple watch for a long time now, and i wear it 24/7. at some point, I noticed that the apple watch created a concave hollow on the top of my wrist. and this deformity is not short-term. i tried putting apple watch off my wrist for two weeks and my deformed wrsit did not come back. apparently, a lot of apple watch users have these problems. so what is up with that?

p.s. i dont wear my watch too tight, and the deformity is significant.