@Vikingboy55
I'm led to believe there is some compatibility issues with the external hard drive and this game OR the game is installed on the external while the updates are installed on the internal which is why it keeps prompting to update it.
On Xbox there is an option to designate where you want updates, make sure you are selecting the proper hard drive on where they go. I recommend unplugging the external hard drive and delete any NBA Live data you have on the internal. Then, make sure you select updates to go to your external drive before launching the game again. Once it downloads the updates, try saving the roster in game.
Try launching again. If it occurs again, I would try deleting all data on the external and double-check the internal. Reinstall on the internal to see if there are any further issues.