i reenveloped assaj and fixed all disconnections and uncleanness (and wanted to make her skirt cloth, but thats another story)
as you maybe know there were some poys that didnt show up ingame
i wanted to fix that, but now more than the half of her eyes is missing
this is the way she looked when i imported her:


and now she looks like this:


what did i wrong and how can i get rid of the "missing" polygons?

edit: i have another problem, suddenly i ccan see all bones and objects trough objetcs

edit2: now her head lost the UVs

edit3: i redid the UVs, and the pupil look like in the first picture now

If polygons are missing it means you have to many vertexes to close together. You'll have to make it lower poly in that section.

yes, it works, thank you
but technically it doesnt make sense
if you triangulate a weapon, all polygons show up and on this model they only show up, if i delete edges

If you delete, filter or weld the edges it has to fill in the space somehow (or it will leave holes).
With filtering and welding there is the slider bar you can adjust so it will affect the edges so you can control how much it takes way kind of thing.
If you are welding edges you can slide it to the left as a very small number and still get most edges, there will be at times some you can't weld or filter
if you want to preserve certain features of the model.

Hope that helps