Minecraft resource packs not loading

I'm not sure if everyone else is experience this.

When I load resource packs onto worlds, sometimes the textures don't get updated (chunk bounds texture pack doesn't work but worked in previous versions).

I don't know if this is a bug, or Minecraft files have been named differently in this version.

 

Edit: I tried every resource pack I had and none of them worked, even if I re-downloaded them. And they definitely worked in previous updates, so all I'm asking is if file names have been changed in 1.16.201. If I contact the creator, they'll be confused why it isn't working for them!