Hey again PolyCount,
Just put my model into substance painter just to see if everything looks alright, then when I started painting I noticed parts of my model were dissapearing and that some of my UVs were missing.
Also if you were one of the people that helped me with my previous problem then thank you. I didn't reply to the post because I didn't want to bump it back to the top.
EDIT: Nevermind, i'm an idiot. Found the solution a couple minutes after. Turns out that the materials I applied for an ID map were making parts of my model dissapear when painting.
Replies
You can disable that feature. Go to Edit>Settings and uncheck "Only display the selected material when painting"
Happy painting