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.
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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