How to restore (re-upload) deleted cloud data?

If you tried to clear up some space in your iCloud, you might have accidentally deleted the cloud storage of NotePlan on Apple's servers. This can happen if you clear data under "Manage Account Storage" on iOS (NotePlan might still appear as "NotePlan 2" there, but it's the same storage NotePlan 3 uses):

Or on Mac, when you manage the iCloud storage:

If you have deleted the cloud data, you can still sync and keep using NotePlan, but it is recommended that you reupload all your data as a backup or when you want to sync a new device up to date. 

Reupload your data to the cloud

If you are using CloudKit, open the preferences and navigate to "Sync". Then click on "Advanced" and upload all your notes using "Delete Cloud and Re-Upload":

You need to do this only from one device. If you open NotePlan on another device it will sync with the re-upload automatically. You just need to wait.