Verify Locations have been set up properly.
Verify Items have been set up properly.
See:
https://support.heartlandretail.us/en/articles/94544-how-to-set-up-your-management-one-integration
Click Dashboard
Click Settings
Click Integrations
Click Management One
Key in the Management One Client ID
Select the Start Date
Select the End Date
Select the OTB Class Field from the drop-down menu
Select the Export Grouped By from the drop-down menu
Select the Export with permanent markdowns from the drop-down menu
Click Export