Need roll not possible.

[Clavaat]

-snip-

A lot of early gear has All Classes as the Required Class. That's why you were able to Need on them (that's an important distinction, you can Greed on anything, but you can only Need on gear from your Class). As you go along, gear will be more Class or Job-specific. So no, you didn't do anything wrong and it wasn't a bug, that's just how the loot rules are. You can still try your luck on Greed, for other jobs.