You would need to:
1. Confirm that you have set up your Mandrill account
Here is a Guide on how to set up Mandrill
2. Confirm that you have defined a reorder level for your products.
Here is a Guide on how to set a Reorder Level
Contact the Support Team via Email at Support@ecomdash.com if you have confirmed the steps above and still aren't receiving low inventory emails. Please be sure to include the SKU number of the product that you aren't receiving low inventory notifications for.