Ran into this problem today, which is similar to the problem noted in my last entry to the 'problem index' in my first post.

Booked ticket for my children using points. Filled out purchase form and clicked 'purchase.' I fully expected the UM pop-up asking if the traveler was traveling with an adult companion or not. Since my daughter is traveling with me and mom (who is traveling as my companion), I used my wife's PNR to avoid the $50 fee. When I was redirected back to the purchase screen, not only was the credit card info blanked out, but all the passenger information (including RR number) had now changed from my daughter to me! When I corrected the passenger info using the available link, that action must have reset something as when I clicked 'purchase' for the second time I was looped once more in the UM pop-up. After putting in my wife's PNR a second time, once returned to the purchase screen (for the third time) all the information was correct and I was able to purchase the ticket.

The same thing happened when I tried to book a ticket for my son only that instead of all my info being used as the traveler after associating my wife's PNR to the ticket, only the RR number was wrong: it inserted my RR account number, but at least my son's name was still there. Changing the RR number resulted in the same pop-up behavior and me having to reenter a PNR a second time to avoid the UM $50 fee.

And each time you're redirected to the purchase page, the credit card information disappears, of course.

I don't know if this is a browser issue, only happens when you try to book with points, or only occurs when you use a companion PNR to avoid the $50 fee vs. the companion pass holder's PNR...