Place it as the response beat right after the on-screen request appears, then follow it with the no no wait wait button when the other person tries again. For a second refusal round, end the sequence there instead of stacking more reactions.
Über diesen Sound
A 1.5-second German voice clip of a woman starting the sentence 'Könnt ich, aber...' and trailing off unfinished. It feels dismissively funny, like an excuse being made before any help is actually offered. The line comes from the 'Computer Says No' material in Little Britain, also credited as Little Britain USA.