Wierd normals when modeling inside mesh ?

Ok so i have no idea how to approach it.
Usually i just flip the normals, but this time it’s acting weird when i started modeling the mouth…


These are the areas.

And the normals


I think this part is what caused it if i’m not wrong.
Any idea why this is happening ?

EDIT : Sorry for the big images i can’t upload attachments.


i watch the blend file… flip the normal manually using the property panel because use recalculate the normal don’t work. use only flip normal on all face that have this issue, i think its, duo to the topology of the mesh.

Thanks @ rebellion.