What behaviour is observed:

Sometimes when player join in server he losts their skin. On world change player's skin restores.

Steps/models to reproduce:

I don't know, it's causes sometimes. I do not see dependence.

Environment description

Bungee, MysSQL

Plugin version or build number (don't write latest):

3.0 (i compiled for my own from github)

Error Log:

Hastebin / Gist link of the error or stacktrace (if any)
there is no error

And which commit did you compiled?

c362131

Does the player loses the skin if the player joins directly or during a server switch?

joins directly

I think it could be a timing issue. Do you have server blacklist enabled?