Hello, I`ve started making my own texturepack recently and encountered a problem. Non-Latin symbols (Russian) are just squares or dots. Latin symbols at the same time work fine.
I downloaded the asset from mcasset.cloud (1.14.2 if i remember properly), and in the files of the pack all the symbols are ok.
The only solution i know now is to download working asset (but it will take very much time to move all the textures i`ve made already).
UPD. I downloaded a working asset and moved all textures there. It took much less time than I was expecting.
Did you try to set the language to russian, where as it will use russian font in the default resources?