Not that long ago (roughly a few months ago), the Orsinium DLC pack came out on the Crown Store, and since I had already bought the Imperial City DLC pack, I thought about getting the Orsinium one too. I had to get some crowns from the ESO game website because I only had 600 Crowns left.
I had used a prepaid debit card at first, and when I attempted to complete the purchase for about 5500 Crowns, it said "The transaction was not authorized. Please contact your payment provider for additional assistance." I know for a fact that the card had enough money in it for the purchase, because it had $50 inside it, and the 5500 Crowns cost $40.
I then tried it with a normal debit card instead of a prepaid one, and I got the same message "The transaction was not authorized. Please contact your payment provider for additional assistance."
I submitted a ticked, and tried doing my own research on the topic. The ticked ended with nothing happening, and my research led me to find that in the past a lot of people have had the same problem as I. Some have gotten their problem fixed, and others I believe have not.
I thought about starting a whole new account and seeing if that would fix it temporarily or permanently, but since I had already bought the Imperial City DLC, I didnt really want to have to re-purchase it, simply because the ESO website has a problem with my account. (I also know for a fact that its the website and not my card, because I then used that prepaid debit card to purchase Skyrim on steam, and the normal debit card to purchase other things I needed. They both worked fine.)
I would love to continue playing this game, but at this rate, the only content I will be able to have is the Imperial City, and the normal game. Right now that seems to be 2/3 of the content, so it inst that bad (Assuming that IC, and the normal game content are counted as 1/3), but as more DLCs come out, and as the rest of the continent of Tamriel is unlocked for players, that is going to be a lot less content available to me. Any help is welcome at this rate.