In pretty much 100% of that cases I've seen, it's saying 44 because the person was actually missing one, even though they thought they weren't, usually because they were looking for one in the wrong spot, and so assumed it was one they had gotten.
In your case, you're missing [url=https://lowlidev.com.au/destiny/maps/mars/4073240388?origin=d2checklist]this one.[/url]