You may need to submit a support ticket on this issue if you haven't done so already. I would really need more information such as, what does Notion say it is doing just before the crash occurs? Something you can try is to go into "Go" on the Finder menu bar, hold down the "option" key on your computer keyboard until you see "Library" appear. You can then go into Library/Preferences and delete anything that starts with com.notionmusic. This will remove all of the settings for the program, so you may need to re-configure after doing so.