@Desiree224 Hello! Did you try the suggestion from PoptartJuniper? There is a limit for the library on console. I believe it will vary depending on how much free space the system has. So, from the home screen, open the Gallery / Library and delete some stuff. Perhaps there are duplicate households that were saved when creating a new save? Or you may just want to delete anything that you aren't using in your game. Note that you will not be able to recover anything you delete there but, if you have access to the Gallery, perhaps you could upload some things you want to keep and then add them back to your game later.
As you mentioned, this thread is a few years old now, so it may get locked. If that happens and you're still having trouble, then you will need to create a new thread.