I’ve been having this issue since before the IT “upgrade” (inverted commas used because it will likely result in anything but).

At first, it would accept the info only for next time in MMB I would see the same prompt - all info had been wiped clean.

Recently though there is an error with my information apparently - it cannot be associated with a particular segment or already flown segment… nothing else to help one even make sense of what is wrong … I’ve resorted to Twitter and the useless chat bot, hopefully a human picks up my DM as I fly to the US on Saturday. Managed to enter it all once on the AA site for my transcons on AA without any issue.