I think you are leaving something out. If the Falcons were already winning and got a TD, once score wouldn’t be enough. Was their an onside kick?
Here is the article describing what happened
https://www.google.com/amp/s/www.cbssports.com/nfl/news/look-todd-gurley-costs-falcons-by-scoring-td-after-failing-to-stop-his-momentum-leads-to-wild-lions-comeback/amp/