I used the term mistake to indicate there was a problem. I did not go in to the reservation and accidentally clicked change to advance purchase then hit submit.

If you open two reservations up at the same time, and modify the first one that was opened, make changes and hit submit, the page fetches the most current reservation ID stored.

During my process the page never reflected the latter reservation code, it is only when i hit submit, once the page refreshed that it showed up.

This wasn't an oops on my part, i never anticipated the system would act that way, i definitely never anticipated my existing session that i am working on to update the other reservation id behind the scenes after it refreshed. As it continuously showed the previous reservation id on the screens.