Can't use overlay method on powder snow

[pazuchi214]

I'm trying to make a resource pack. I want to use overlay method to make powder snow look spreading, so I wrote a .properties file for it, but it doesn't work. The same .properties file works for snow block. I wonder if this is a bug, or I've made mistakes in the .properties file. The game version is 1.20.1, and mod version is 3.0.0 using connector 1.0.0 beta.46 in forge. Here's my .properties file: