Unable to load .fbx or .gltf file

I have 3 files to be loaded into the scene (.stl, .fbx, .gltf). All these files are located in the same directory.
I am facing no issue while loading .stl, but for .fbx and .gltf I get the error 404.
Not sure whats causing the issue, as file name and path seems correct. I even tried reading .txt file from the same directory with no issues whatsoever.

Hi, it would help if you share the code or screenshot of what you see in the console and in the network tab.