While playing fallout 4 since it the game came out, on the 10th. i have about 6.9 days of in game saved data in which now my xbox for some reason didn't save 3 days of in which now its trying to sync and its taken 2 hours to sync only to freeze up at 99% and xbox networking is saying now it maybe a bethesda issue. anyone else having this issue? and if so, what did you do to fix the issue? i hard reset the xbox and even reinstalled the bloody game and still its not fixing the issue. Any responses that can help would be appreciated, thanks!

I had this problem, and here's what fixed it for me:

1) Go to settings, then network, then choose "go offline"

2) Restart your Xbox One using the snap menu

3) Sign out if your profile if you have auto-sign-in enabled

4) Settings, network, go online

5) Launch the game, confirm your profile when it asks who you are

6) Data should now sync, you should be good to go

Edit: added step 2 , I forgot that bit.