So I just got back on to BDO and tried to turn in some quests but when i tried it just said "Cannot apply item results to memory." I also tried to forfite the quests but also couldn't and it says "Cannot find the quest data" I have no idea what to please help. P.S. it says the quests are from the black spirit on the quest screen but when I do the "Move to" action it leads me to some guy that I'm pretty sure I got the quests from.

I am having the same problem. Did you ever find a solution? 

Do you have the titles of the quests that the issue presents itself on? 

Whats worked for me is to forfeit the quest and restart it, and also there is something about if it involves turning something in sometimes you have to cycle the chat, quest button in the right order before it will let me turn things in.