Conjured Arrow +4 bug

Hi all,
So I’m trying to get the extra xp from the Hunter achievement where you have to draw six cards from one conjured arrow. I’ve done it a few times now and still it’s not awarding me the achievement.
Has anyone else run into this?
The first time I did it and it didn’t work I couldn’t remember if my hand had enough room when it went off for all six cards, so after seeing it didn’t get awarded, I just played again and made sure I had enough room to get all six cards. I actually got it twice last game; the first time for exactly six damage and six cards and drew all six, then again for 11 damage which drew over six and killed me from fatigue.
I’ve never gone after achievements before and it kind of sucks that the one time I try it doesn’t seem to work.