They don’t fix bugs for individual characters unless it is a known recorded bug, and the Devs give them permission - which is rare because it normally makes things worse. Your only option for bugs is to report them to QA via the in-game bug report tool, or the Bug Report forum. Tickets are not how you report bugs.
If it is a bug, it will get fixed when the Devs fix it, usually in a patch eventually.
Usually though these things are due to phasing or quests that are not completed. Sometimes killing the character can drop unwanted buffs. Other times you have to finish a quest chain. Wowhead is usually a good place to search for info.
GMs are not allowed to give game hints.
EDIT - I did a quick search and found something that might help you.
Seems that person solved it by joining a non rated arena match and it went away. Other options might work too.