Trouble Exporting My Animated File To .fbx

Hello, I’m still new to Blender and Unity and I’ve run into a problem.

I have created and animated a Shotgun that I want to import it to Unity. From what II know you export animated Blender files to .xbf, and that’s what I’m trying to do. However, when I attempt to export to .xbf I’m getting this error and I’m not sure how to get past it.

870animation.blend (1.35 MB)