I'm experiencing the same issue with Battlefield 6 on Xbox.
I progressed through the campaign to the mission "Night Raid", but the game no longer recognizes my progress. It only offers the option to restart "Always Faithful", as if I had never completed the previous missions.
My Xbox shows 4.0 MB of saved data associated with my profile. I always use the same Xbox account, and I have already restarted the console and checked for game updates.
Is there a way to restore my campaign progress without deleting my saved data? Is EA aware of this issue, and is there an official fix?