Julia 1.6.7 LTS Pkg.add("Gtk") on Windows 10

I am trying to install Gtk, but got an error message as below.

ERROR: Unable to automatically install ‘adwaita_icon_theme’ from ‘C:\Users\me.julia\packages\adwaita_icon_theme_jll\YjPmX\Artifacts.toml’
Stacktrace:

I am behind corporation proxy, but still able to install other packages.
Does anyone have the same problem and resolved it?