Once you move Inventory to Reorder to the Show List, it should appear in your Reminders. Please review it and ensure you select OK after enabling the feature.
If it still doesn't show, please update your QuickBooks Desktop (QBDT) to the latest release and run the Verify Data tool to check for file errors. Select the Utilities from the File section, then choose Verify Data.
If your data has lost integrity, please visit this article for further guidance: Verify and rebuild data in QuickBooks Desktop.
If the issue persists, contact our Live Support team, as they have specialized tools to investigate further.
Feel free to comment below if you have more questions about QuickBooks.