Some Faces are lost after import to Unity from Blender

[Utri]

Hello,
I just started to learn both Unity and Blender and this is the first issue which I encountered and have no idea what is going on. So, I made a model in blender, it has geometry and UV map with the texture. I did an export to FBX in Blender, Here how it looks like this in Blender View and FBX export settings:

Next thing I did is imported it in Unity project (new one, 3D). I noticed that Texture need dropped on the model in the scene view (read it somewhere in documentation), since it is not automatically applied, but even before I did this I saw that some faces are not shown in Unity, here how it looks:

Could someone please point me into right direction what could be the issue here and what I’m doing wrong?

[GuntranHoet]

Your faces are not missing, they are turned the wrong way. The normal of you faces (the direction to which the triangle/polygon looks at) are inverted.

When exporting your model, is there an option that’s called invert normals, flip normals, or normal direction? If so you might want to flip you normals when exporting.

An other way is to manually select you model, and flip the faces in the blender viewport.
(I don’t use blender, but there should be a function to invert/flip your normals when exporting)

Here they also tackle the same problem and found a solution:

My mesh is black. Flip Normals??