Mario and Bowser Thie inside story Freezing at a save point Way into the game

I am not sure if I am in the right place- But here goes- I have this game running perfectly on an M3DS Real card and have been able to save after Bowser Battles the train as a mega bowser and contunue with the story.- On my sons game card- Exactly the same as the other- His game froze at this point. We have startred a new file to try and get back to where we were, But this file is now freezing in the same way after Bowsers first battle with the Castle when he is mega- Any Ideas??? Our original file was much further through the game- Could it be cheats affecting the save- He loves to use them?

 

Yes, that is most likely the case. Turn all of them off. Always backup your save-file if you are to use cheats.