There was a problem during initialization, such as failure to create partitions for the primary source of the data flow.

1. Depending on your installation, review the pr_assign table in the rules schema for any status issues:
   1. Using an SQL tool, run a query that returns the detailed status information for the data flow run.
      For example: Select * from pr_assign where pxinsname like '%work_item_ID%' where work item ID is the ID of the data flow run, for example, DF-1.
   2. In the query results, review the pyassignmentstatus property.
      For an active data flow run, the correct value for that property is In Progress. An empty value of pyassignmentstatus property might point to a data flow activation issue that is independent of Pega Platform.
2. Review the application log files for any issues with the activation of the data flow run.
   For more information, see Viewing logs.

   Note: Before viewing logs, you can change the application logging level to Debug and restart the data flow run. For more information, see Tips for troubleshooting data flow rules.