I accidentally turned off sync on one of my Xbox games: How do i turn it back on?

Hey! I serched it up and it turns out there is a video explaining it so search it up on youtube and go to 45 secs in the video as thats where he starts to explain it

For now, why not just turn off the Xbox at the wall, then sync your controller to your PC, then turn the Xbox back on at the wall. That way you wont turn the Xbox One on when syncing the controller to the PC.

I have this same problem. I started the game while my Internet was off. And yes turning back on my Internet brings back my saves but then how can I connect to Xbox live after I back out of that when it tells me it can't connect? Because I have to disable
my NIC, restart the game, load into my save, and then turn my NIC back on. So how do I force a sync after that? I can't find a menu or anything in the game to try to get it to sign me in again.

I had this problem before but I got it working after a while. Try turning off your console and turning it back on. Then, press the 2 sync buttons, one is on the controller and one is on the console itself, at the same time. If that don't work, turn off the
console again and turn it back on and try to press each sync button in a different combination. Hope this fixes your controller problem.

Here what I found around on how to fix this issue:

Go to settings and turn your Xbox to offline mode - Turn your xbox completely off - Turn it back on and sign out of your profile - Go to settings and turn if back to online mode - Start up Fallout 4 while signed out - When it forces you to choose your profile,
do so. The game should sync at this point

Seems it works for many gamers.