Ive got a truck and some faces I made are flipped but no matter which way its flipped it always is invisible in unity

I tried deleting the face and remaking them but that doesn’t really fix it.

Hmmm, this is weird. Mostly this problem occurs when you have the face facing the wrong direction, but after flipping it in your modeling software it should be fixed. For example in Blender when your face is facing the wrong way, it’s darker than the other faces.