Dissapearing object

So I’ve been working on this for a while and I don’t understand what’s going wrong.

I’ve modelled a human hand skeleton, and set up the armature and a few animations so when you press a button a certain finger moves. However, one of the bones disspears when you run the program. When in blender you can see the bone, everything moves fine and there’s no problem. But when I run it as a program it dissapears.

WHY???

Thanks For your help

Hello
maybe a “wrong normals” problem?!
Enter “Edit Mode” select all vertexes and press Ctrl-N keys to “recalculate”!
Bye

fixed… I’m not sure what I did to fix it, just changed things on the camera, but it’s fixed. Thanks