KL 1646 then U2 7927 at Schiphol
Genova → Amsterdam → Prague
Timetable, Amsterdam time
16:05KL 1646 from Genova at the gate
13:10U2 7927 to Prague leaves the gate
21 h 05 apart on the timetable, overnight
U2 7927 leaves 21 h 05 after KL 1646 arrives on the timetable: more than half a day, so not a connection we count.