Two different things. The warnings to backup when exit are set in preferences.  Even if scheduled backups are on you can be reminded to backup. Some firms like both and if you are not making sure your scheduled backups ran correctly then it’s an especially good idea to periodically do backups manually. The second message relates to paths for backup and scheduled back. It could be because you have never done a manual backup, or a setup issue with your paths or schedule Le backup. Would need to check all elements.