NamelessMC

Hi, in my server I use JPremium as a plugin for player authentication, but it assigns to each player a different UUID than the original one, and when the players register they take the fake UUID without skin, if I update the UUID they take the skin but they are no longer connected to the account on the minecraft server.

How can I fix it?

I saw, if I'm not mistaken, that the skins are taken with the following link "https://sessionserver.mojang.com/session/minecraft/profile/" but it requires the UUID, is it possible to do it that requires the nickname?