Oh forgot to mention it in my post above.
Any of the new premium items… bazaar / battlepass stuff… they require constant online sync with the Funcom servers. So at any point where your connection to the Funcom live services drops even for a tiny bit (even if you’re still connected to the game server like normal), you won’t be able to use any of the premium items even if you bought them legit.
That could be what you’re experiencing, if not and it’s a permanent thing that you can’t fix by restarting the game and your bazaar is functional (when Funcom live services are down the bazaar page usually doesn’t work well) then it might be a bug, however if it’s what I described above, then sadly it’s intentional 
(Basically what I’m saying is that contrary to old DLC stuff, your entitlement to these items are stored online on their servers… and any time you try to equip / use anything… that’s where the permissions are being checked, not on your local computer)