Backlog shows cards that cannot be found in browser

[student]

Anki 2.1.47
Windows 10
Addons Disabled

On the stats screen, it says 87 cards were due 23 days ago. I clicked on the column, but no cards were displayed in the browser. Please see the screenshots below.

Any help figuring this out would be appreciated.

[student]

Problem solved.

The 87 cards were in a filtered deck. After emptying the filtered deck, I was able to click on the backlog in the stats screen and have the cards appear in the browser.