I have had this happen I think 2 times. All you have to do is go to your account and update the billing information with the new card's number. All they do is put your account back to basic access when you fail to pay, heck I even failed to pay for nearly an entire month because the bank cancelled the card I was using due to their own security leaks... Disney still didn't cancel my unlimted access. I gave them a call and they told me the probelm was their fault for not going ahead and canceling my account, and I got a month of POTCO for free lol... Then they started charging my new card, and as Zeppers said earlier, I got the first month on the new card for $4.95. Just give them a call, tell them what happend and you can get your unlimited access back it isn't that hard.
The only thing I could think of that might have happend is you have gave them bogus information, then that is on you.... I just hope that isn't the case.
Larence Tuppington