Guild Wars 2

This has been happening to me for a long time, I just always thought it was probably me doing something wrong somehow.

I play a thief too and when this happens I tried everything listed above. Go in stealth to try to drop aggro, defeat a random nearby mob to try to drop it, run away and more stuff, it all doesn’t though.
It’s especially annoying when you want to travel to a way point for instance but you can’t because it says you’re on combat…
Today it REALLY pissed me off though as I tried to get in the halloween jumping puzzle map but couldn’t enter the stupid portal after defeating the keeper of waves because apparently, I was in combat. Before I could get out of it (after like 2 minutes) the portal had already disappeared…

It also annoyed me in boss fights or any other strong creature. What would happen is I would go in hiding as my health depleted just to regain a little and the enemy took like 3 seconds to get out of combat mode and auto-regenerate most of his health. Why do the monsters go in regeneration mode after 3 seconds while I have to wait several minutes to get out of combat mode?

PLEASE fix this, it has made me rage more than once in this game.