Pinching under character's arms in Mixamo

[andrewc68708444]

Hello all
I have this character I made using Nomad Sculpt, and when I use it in Mixamo I get a pinching issue on their upper body. I was wondering if anybody knew why, or how to fix it? Thank you 

[Ussnorway]

its caused by your weight map lifting up as the arms move and the fix is to make the model in T pose next time instead of A pose... or you could just redo the weight map in something like Blender