My friends have loaded up on the realm that I own and have a texture pack that we have running is the natural texture pack, not vanilla. And they have come across it as the original. I have gone on to update the file and to see that it isn't working, I have tried taking it off and loading it back up and it isn't working at all. It only started happening as of 8/9/20 and it was about evening time that this had happened.

I have also tried the Skyrim texture pack and this also reverts back to the original/vanilla style. 

Not sure if an update has messed this up or not, or server related. Hope this helps.

Nova.