KL 1820 then U2 7927 at Schiphol
Frankfurt am Main → Amsterdam → Prague
Timetable, Amsterdam time
15:30KL 1820 from Frankfurt am Main at the gate
13:10U2 7927 to Prague leaves the gate
21 h 40 apart on the timetable, overnight
U2 7927 leaves 21 h 40 after KL 1820 arrives on the timetable: more than half a day, so not a connection we count.