UA 3905 then UA 417 at Houston
Cancún → Houston → Los Angeles
Timetable, Houston time
13:29UA 3905 from Cancún at the gate
06:10UA 417 to Los Angeles leaves the gate
16 h 41 apart on the timetable, overnight
UA 417 leaves 16 h 41 after UA 3905 arrives on the timetable: more than half a day, so not a connection we count.