Hi @Asta-of-the-ice, welcome to the community.
Please ensure that your save is stored on the XBOX cloud before trying each of the following steps and letting us know if they help:
Reset the console cache by holding the power button for about 10 seconds until the console powers off, then disconnecting it from the power outlet for a couple of minutes, then try loading into your SP session.
Try to perform a soft factory reset while keeping games and apps.
If the above procedures don’t help, would it be possible to try installing the game to a different drive?