Why do some of my sales show as Uncategorized in the Sales by Category report?

Sales by Category groups each sold product under its primary category. A product lands in Uncategorized when:

• it has no primary category set, or
• it has been deleted since the sale, so Wcart can no longer look up its category, or
• its category has been deleted.

To fix it for future reports, open the product under Products, set its Primary category, and click Save. Past orders then group under that category as well, because the report looks up each product's current category every time it runs.

To open the report: Open Marketing → Marketing Home and click the Reports tile under Measure. Then click View all → next to Sales by category.