Game losing its save after a Horizon Arcade event

This was a bug i encountered when trying to do the Flying Customs treasure hunt.
After the event, went outside, came back, game closed., went back in the game just to see that the map doesn’t show the treasure chest area, i no longer have the Pilot Things accolade, and its gonna take me a LONG time to get an Air Horizon Arcade event.
Just to summarize it, i lost the last save and its on the 2nd last save, any fix? (Also, this is all on the Xbox One)