I likewise am having the same problem and have reported it a few times :/ It's getting quite frustrating as i'm lvl50 now but unable to unlock any of the later dungeons to join my FC and friends orz.

Frequency: always
World name: Coeurl
Character name: Aleksander Neige
NPC name: Joellaut
Monster name: none
Class/Level: Scholar lv 50
Party or solo: solo