You should open a bug report for it since this could be an account bug rather than the game as a whole. Not much anyone on the forum can do about it.
abjectarity
Lord
Insider
You can only hold one at a time and if you already have one it doesn’t show it on the second page for purchase. Check your quest inventory to see if you already have one. They gave everyone a free one for logging in this weekend, so if you haven’t used that one yet… you already have one.
HiradC
Legend
Insider
Worked fine for me
Dargis1401
Champion
Insider
Only the captaincy voyages seem to be broken, if you buy them from the pirate lord they should work.
PithyRumble
Rogue
Insider
I got my voyage on my main and my 2nd had one in pocket. I heard they weren't working right so I let them simmer.