No one met this problem before? Or the screen recording doesn’t work?

I have some guess, can you show the path? the entire vector layer? or send me a copy of the file just put it on drafts the share on view.

Thanks for replying! It’s a single flatten path. Please check the link attached

You need to re-union(merge) the path because there are 2 paths on your current vector file.

Current vector has 2 paths: 

After union it will be merged into 1 path:

thank you so much!

So it was not a single path. I wonder if it only can be distinguished through its code? It’s hard to find difference visually. 

To be honest, that’s not what is expected for Figma to behave. Because both colors uses the same variable so both should be modified simultaneously and not just that one path when you changed the variable, I’m just not sure what happened. You can try flagging this with the Figma team and see if it’s intended.