Games not saving - or previously saved games not appearing - has been reported by many Mac users.
Some Mac owners have reported this solution, which has worked for everyone who's tried it.
Check this path in the Mac: System Preferences > Security & Privacy > Privacy > (scroll down to find) Files and Folders
Make sure the "Documents Folder" (under the game that is not saving) is enabled (the checkbox must be checked).
If the folder is not enabled, make sure to enable it, then try playing and saving the game.
If that fails to work, please check to ensure the computer's disk is not close to or at its maximum storage (an obvious, silly idea, yes, but in our experience often the obvious or silly is overlooked).