Nostalrius Begins - Quality wow vanilla realm (1.12)

Hi,

i was leveling my character and disconnected from server.
now if i want to log in the game tells me my account is closed.
what did i wrong ?

Greetings!

Your account was banned for botting. This is a permanent ban.

Sincerely,
Ithlien

I've never botted i invested so much time in the character
to get a high lvl. was grinding because is dont find any qsts