This has been happening to some people here and there, I suggest just putting a support ticket in to Zeni. People have indeed been getting crowns repaid to them from subs that didn't come with any.
Beware the battle cattle, but don't *fear* the battle cattle!
People have also been reporting getting the run around from Zeni if those crowns are purchased through Steam, with ZO and Steam support both telling players there's nothing they can do and to talk to the others.
Definitely submit a ticket. If that doesn't work and you paid by credit card, contact your card provider and challenge the charge on the grounds you didn't receive what you paid for.
If you didn't pay by credit card then you're down to trying third party agencies like BBB (who in my experience are very good) or your local consumer protection agency.
Hopefully they'll just fix the problem for you though.