Place it straight after the incoming text or call appears on screen, so the refusal answers that moment. Follow it with Nope for a firmer shutdown, then use Okay Let's Go when the character walks away and ends the exchange.
이 사운드에 대해
This is a short spoken clip lasting just over five seconds, built around the dismissive line 'new phone, who dis?' delivered in a flat, unbothered voice. It feels cheeky and cold at the same time, like brushing someone off without raising your voice. The humor comes from how casually it pretends not to recognize the caller.