I used blender to create a low poly version of my sculpt and it's parts. I then combined all the parts to have them all in the same uv map, but when i imported it to substance painter all the uv maps are split back? You can even see the spaces where the uv islands are missing on each texture set. Is it because it's exploded? I'm still new to 3d modelling and just started with texturing.
EDIT: found out that it was because my parts had different materials that i used to test the uv stetching. I cleared them all and it merged properly