You need to create proper material.
Create material that uses only DIFFUSE and normal map (keep that metallic, ambient, roughhness in material, just not connected).
IF that helps you know its something with that ambient occlusion texture.
Add multiply nodes, and scalar parameter with how much you multiply it.
Create material instance and play with multiplayer values
And try (double check) if albedo metallic and roughness are connected to correct RGB pins.