JL 6750 then VN 311 at Narita
Seoul → Tokyo → Hanoi
Timetable, Tokyo time
09:33JL 6750 from Seoul at the gate
09:30VN 311 to Hanoi leaves the gate
23 h 57 apart on the timetable, overnight
VN 311 leaves 23 h 57 after JL 6750 arrives on the timetable: more than half a day, so not a connection we count.