Help - How to fix this texture?

Hi, I have this very simple object, inside Blender it looks ok but when I export it as a .glb two of it sides come up with streched textures. (the same material works fine for the other sides)

Even or because this is you first time:
The community has to download 19MB to have a look at your problem… and you aren’t able to discribe it in some words or even an image (and i don’t mean a 6MB image in which one can see mostly the blende GUI ??) Or maybe just make the texture smaller (because the object is simple)???

In Cube the sides have different sizes in UV space so they are (of course) stretched … and you want those super multi n-gons …?

Hi, sorry about that, I tried to upload but it told me that new users can’t upload files to the post.
Ok I’ll check that, I tried moving the UV map all around without fixing it.
I will figure out how to make better posts also, sorry-