Can't start Digital Game

Have you tried restarting and or a power cycle on your Xbox One console?

https://beta.support.xbox.com/help/hardware-network/power/restart-or-power-cycle-console

Usually with a cloud save problem you should see an error, see https://beta.support.xbox.com/help/games-apps/troubleshooting/cloud-storage-sync-error-messages

Have you tried deleting and re installing the game yet?

You can delete cloud save via:

You can manage your data for individual games through My games & apps on your Home screen. Here's how:

1. On Home, select My games & apps.
2. Highlight the game, press the Menu button  on your controller, and then select Manage game & add-ons.
3. In the menu on the left side of the screen, scroll down to Saved data, then highlight the saved data for your gamertag on the right and press the A button  on your controller.
4. You'll be prompted to confirm deletion of this game save data:
   • Delete from console removes the local copy of this save. You can get it from the cloud the next time you play.
   • Delete everywhere removes your saved data from this console, the cloud, and all other consoles you play on.
   • Cancel leaves your data intact.

Just going to answer my own question, for xbox 360 games, start the game. Go to the 360 guide and manage storage. Delete the save, it'll reset where you were at, but you can at least play the game again.

I've tried to reinstall. Doesn't work. As for deleting saves from cloud, i don't know where you guys get that from, but there is no such option on my xbox one x.

I've seen that same answer before, but I just can't seem to access my cloud saves. Is there a website or something to delete it?

Honestly it sounds like there may be a glitch with the way the game installed, I would recommend a full power cycle and if that doesn’t work remove and reinstall the game.