Bug Reset Achievements
From that screen, unless I am missing something, it could be inferred that you don’t have World 1, Zone 3 complete. If you do, in fact, have both achievements for Zone 3 (not shown in the portion of the panel in this screenshot), then report it as a bug and maybe open a ticket. (I don’t know they would be able to change anything for your account, but at least they can try to see what happened.)
Good luck.
It seems to have fixed itself in the last 24hours, so I take it re-logging fixed it or Anet did, either way it is fixed.