When editing settings for multiple activities, you can select a setting that isn't valid for all the selected activities. The Settings Conflict message alerts you to the fact that your setting could not be applied to one or more activities.
For example, you might have tried to set several activities to graded, but one of the activities was a video that can't be set to graded.
Resolution
This message is informative only and does not indicate an error. Usually, no action is required.