If your sales report shows many products that say "Not Set", that indicates these products did not have a lot cost set at the time of sale.
This is most common when looking at Sales Reports for a time that was before Shopventory was installed. Shopventory does not know what your products cost before we were managing things, so no retroactive profit calculation is made automatically.
Using the Current Default Cost to Backfill Old Sales
In the Advanced tab in the Settings section of Shopventory, you'll find the option to use the current default cost for all sales that don't have a cost entered.
Once a product's historical sale costs have been backfilled those costs cannot be altered so make sure you have the correct default cost entered in the Edit Product panel before you run this task.
Please start a chat if you're not sure this is the right task for you. We are here to help!