Nostalrius Begins - Quality wow vanilla realm (1.12)

Hello,

As title says, I cannot banish any hostile warlock pets...
When i try to banish a pet, all i get is just "invalid target" message.
Asked some locks if they r experiencing any similar issues and looks like its just me for some reason.

Any ideas?

Edit: Typo on title

First thing you should do when running into issues is turning off your WoW client, navigate to your World of Warcraft classic directory, and delete your WDB and WTF folders. Then, log back in your account and disable ALL of your addons. Once thats done, log in your character. These "bugs" usually occur because of a cache issue or some addon. Let us know if that helps.

Yeah I did what you suggested, but without any success.
Cleared everything including interface folder, wow client went back to its default settings and issue still persists.

This is a server side bug. Enemy pets being unattackable due to invalid target has been around for quite some time and there is nothing you can do clientside to fix it.