DL 2398 then DL 5699 at JFK
Atlanta → New York → Washington National
Timetable, New York time
17:36DL 2398 from Atlanta at the gate
15:00DL 5699 to Washington National leaves the gate
21 h 24 apart on the timetable, overnight
DL 5699 leaves 21 h 24 after DL 2398 arrives on the timetable: more than half a day, so not a connection we count.