After a while playing on a server, the skins just stop of load (new players joining, NPCs that teleport you to minigames, etc) and everything turn into Steve's skin.
I thought it was the server's problem (Mineplex), but I joined other servers and they all have similar behavior.

In the moment we enter on server, the skins work correctly, but after some time or action like teleport to minigames they stop to loading.

I don't know if it's an old bug but it affects the user experience, seeing everything with Steve (not that he's not cool 😅), but becomes tedious.