broken world/modpack?

[1zzy4u]

I'm using Aternos as a server for AOF 5, and I'm having complications after the world worked well for a week. Mobs don't have moving abilities (Colelytra don't have their flying animation; modded animals move while sitting down). Villagers don't show their professional clothing, but when clicked, they show their trades. All variants of the mobs are the same, even if the mobs have different varieties. The mobs are broken, and it wasn't like this when the server was first created. I've tried restarting the server multiple times, uninstalling it, and reinstalling the mod pack. I even tried making a whole different world to see if the problems happened there, and it was the same. I need help trying to fix this or finding the problem.