Problème of acces to my worlds on Xbox

Hello,
I no longer have access to the world I had already created. The worlds are greyed out and when I try to play on them the following message appears: "The world is not fully synchronised or has been corrupted. Try to play in this world on a console where it is still running and then try to move it again.
This problem occurred about 1 year ago in 1.15.
Thank you for your help.