Wow, I thought it was just me using my Windows phone. I kept getting Unknown TAP error every time I tried to complete the transaction. After first losing 2 GA tix to a MSG show, it forced me to enter a credit card (and I have had an account for years), then proceeded to tell me the card was already associated with my account! How do you knowingly give up 2 GA tickets for the sake of trying again with no guarantee? Ultimately I was able to get them, but now I'm looking to trade for an MSG pair of seats. Feel free to pm me if you have 2 seats and want 2 GA for July 22 in NY.