Why did my Activity rank drop?!!

2 days ago i had Activity rank: Envoy and then you change my Activity rank: to Agent and i donated you and i was online every day!!!

Activity rank depends on achievement points and account status. If you sold or deleted a character, your achievement points might have gone down. But it counts only unique achievements so it won't happen if you have the same achievement on another character. Is your account status in good standing? If not, that's why it's lower. Your account status changes if you get banned and remains that way for 1 year.