Yeah, I've been getting this error all day. was literally on the other night and the game was working fine. I purchased the ultimate edition on launch and thus the edition xbox made me repurchase was the $99.99 Ultimate edition. even after repurchasing, still getting this issue.
naturally like OP said, it's working fine on my other account. I hardly get days off and was excited to be making my Lahn and then actually being able to play but it's looking like that's a pipe dream at this point.
UPDATE: Black Desert customer support messaged me back finally and told me this is a ban because after having purchased both the Ultimate and Standard edition, I refunded the Standard and kept the HIGHER tier edition, I'm being banned for having been refunded and getting the items from the LESSER edition and thus am UNABLE to play the HIGHER priced edition. I now would have to REPURCHASE the standard and not touch ANY of the items THEY send with it for the entire DURATION of my play of the game or else I'll be banned again aka I'm being nickel and dimed. I'm imagining that because THEY foolishly don't offer an ability to simply upgrade editions for the rewards for higher editions, that people have pretty much been buying the Ultimate edition, redeeming the items and then refunding the Ultimate and buying the Standard pretty much getting the Ultimate Edition rewards for the Standard Edition price. Of course, via the response from their own GM, they've acknowledge that I refunded the STANDARD and actually kept the higher priced edition even to a point where I just purchased ANOTHER Ultimate in good faith. I'll probably now be seeking an entire refund across the board and not touching this game ever.