Hi Max!
Not sure if this is a bug or user error, but we've had a couple of emails from users regarding difficulties signing up for payment tiers from free accounts. Seems both times these were for the "Captain" tier. I've attached screenshots, as one of the users has expanded on what the error was as well as the emails they received as a result. I thought it might have been a country related issue but I think one of the users is in Australia so it seems doubtful?
If it's something that can be looked into, that'd be great :)