Workflow not sending Notification to distribution list because they are Cancelled

Hi,  I've created a custom workflow and when it was implemented it set the notification to a distribution list to Cancelled and the individuals are not getting the notification.  This is only happening with the one workflow.  All other ones I've created using the same logic to send the notification to people on a distribution list are working as expected.  I've checked all setups against the ones that are working and the new workflow is setup the exact same way as one that is working.  What could be causing the notification to be set to cancelled immediately?