How to convert UNITY3D files into OBJ,How do I open and edit/convert UNITY3D files?

For starters; I have zero to none experience in Unity. I’m a visual artist who has only dabbled in 3D with Maya and Blender many years ago. I have acquired a .Unity3D file type and I’m baffled that Unity can’t open a file that it created.

I purchased a 3D model from Hero Forge that is easily imported into Tabletop Simulator because of the file type, but I want to convert the model into .obj to be edited or used in other programs.

I could purchase the file again in .stl form, but that would get rid of the colors and texture which was the main point of buying the UNITY3D file format instead of STL.

What are my options?

@Talik13 I think you bought the tabletop simulator asset pack file, not the 3d print model. the asset pack is a digital rendering of your model meant for use in a simulator environment. I had a friend do this a couple days ago. He contacted Hero Forge and they made it right. Solid company.

@Talik13 Curious if you ever found an answer to this? I just did the same thing thinking I could edit the model posing. Losing all the colors would be a pain.