I am sorry if I am being dim, but I cannot see the booking class for my tickets in MMB. I have checked the "print receipt" and "view booking" panes and cannot see it. Any tips?

I need to know because I bought a restricted WT+ ticket to IAH and had to change it. The change fee was large because the flight is next week and restricted fares are not available. I wanted to find out what my new booking class is to see if I can do an MFU. In MMB, MFU is not available to me which is a surprise because the cost of the change of date was so huge that I felt sure that MFU would become available. I want to find out if I am entitled to MFU.

Thanks