Letter Quests Disappeared!

[Madstar]

Ok, I know we can still get the Achievement with the title 'Love Struck'. Each time I ask, people replies ''You can't anymore, it was only available when game launched'' but I see a lot of Newbies with the title. The thing is, I 'think' I did the first Quest for Karin, which was at the beginning with the Drop Box. But now, I searched everywhere, and looked over all Drop Boxes, but I cannot find any new Karin (letter) Quests.

I extremely need it, since i'm going for full Achievement Points (no HammerJaw).

I guess it's a bug, but after reinstalling and rebooting, nothing.

Any help? Thank you in advance.