Place it at the cut where the message changes everything, then follow it with the Bruh sound effect for a deadpan reaction or the Game Show Buzzer sound effect when the reply goes wrong. Keep it as the turning point before the next line lands.
About this sound
This 1.2-second clip takes the familiar Samsung phone chime and pushes its low end hard, so the bright melody arrives with a deep, heavy thump instead of a light ping. The contrast feels funny and overblown, like a routine text alert suddenly demanding urgent attention. It comes from the default notification sound on Samsung smartphones, remixed with extra bass for short videos.