A: "Hi there!"
B: "Yes. How can I help you?"
A: "Can you tell me how to leave a WhatsApp group?"
B: "Just press the name of this WhatsApp group, scroll up, and then press 'Exit group'."
A: "Thanks."
B: "You are welcome."
Few moments later.
A left.
B: "Did it work?"
B: "Are you still here?"
B: "Why isn't my message to you delivered?"
B: "Oh yeah, you left."