It’s a bug, and has been covered before. To summarise what works for me, make sure when you’re playing MSFS that you restart the game every time you play. Xbox will usually have a quick resume function for their games to save loading time between sessions, so avoid this every time you finish playing, go to your home screen and press the start or select button for more options and quit the game before switching your xbox off. That way when you play the next time you will be opening the game fresh. Another point is you can try saving flight every 20mins or so for longer flights, just call it “quicksave” and each save will then overwrite the last save. Then if it bugs out, you just restart the game completely and reload, and use the active pause button to fix your autopilot, just make sure to engage autopilot and autothrusts and move throttle to correct position as I have found in some aircraft that autosave doesn’t always save throttle position. Another tip, is to turn on rolling cache if you have it turned off or to add a little more space to your rolling cache. I think xbox has a default of 8-12GB of rolling cache space available, I would increase that a little bit as it can slightly increase performance and reduce bugs. I’d say set it to a max of 32GB on xbox, so if you’re flying to and from the same airports, it won’t bug out when loading new scenery. Don’t put it any higher than 32GB, as it’s not worth it, I haven’t found any performance increase personally above 32GB, game also runs well between 16-25GB. Good luck