My lvl 90 characters were deleted

Hi guys, after a long time without playing wow (about 5 months) I logged in my account and I see that all my characters in lvl 90 were deleted. But my low chars are intact. I would like to know if that happened to all server or just with me. You know, like a restart, perhaps. If not maybe I have been hacked.
Thanks for help...

You should be able to recover your level 90 through warmane website, if anything you should try to contact warmane support via forums.

Also getting hacked, it was your responsibility to protect your account at all cost.