Anyone know
how to fix this?
The UVs are fk*d.
Either fix them in your modelling package, or fix them in engine using the modelling tool
What if model is skeletal mesh?
Just open it up in Blender or whatever DCC software you prefer, open the UV Editing tab, and click “Auto Generate UVs”. Depending on the texture you plan to apply to this mesh, you may need to customize the UV map further. I suggest that you research this topic.
It doesn’t look like one… 