[ HELP ] Problem With Door Handle!

So I made this in Blender. This, is a door handle. (feel free to provide feedback to make it look better)

It looked pretty fine, until I imported it into ROBLOX (Exported out of blender as an OBJ file)

Then it looked like this.

problem

It’s like it’s not filled, I don’t know why. I’m really in desperate need of help :frowning:

I’m also a beginner in Blender so I have limited knowledge on the controls. I followed a tutorial when making this, (only because of the handle, not the key hole thing) I also used the boolean modifier on this and it’s probably the problem within this. Please help! D:

Thanks for reading! :smiley:

Your normals are flipped.

There have also been countless posts created about this exact issue. Doing a quick search can save you a lot of time in the future.

Sorry, I didn’t know what the problem was :frowning: Any keywords I can search or what exactly I can search about this problem? And uh… how do I flip normals? (i’m sorry, I’m kind of a idiot :sweat_smile:) Thanks though :DD

This thread may help you with your problem: