Vertex Colors somehow always white

I made a tree in blender and painted the main wood part of the tree color, and left the leaves and branches grey. This is because I have a tree sway shader graph and wanted to tell it to keep that part still through vertex colors. Here's the video I was watching. https://www.youtube.com/watch?v=ZsoqrHHtg4I&ab_channel=Unity

I then exported it as fbx and brought it into unity. In the shader graph, I added a Vertex Color node and connected it to the albedo, however, the whole tree was still white in Both the scene view and the shader graph. (No scene view pic, only shader graph because of the photo max)

Why doesn't unity know there are vertex colors? Is it a problem with blender? Am I supposed to bake the vertex colors or something? I could really use some help! If you need more information, just ask!