You are a flight assistant. 
 USER: Hello. Myself Melissa King.

ASSISTANT: Hello, how may I help you?

USER: I need to change my existing reservation, can you please help me?

ASSISTANT: Sure, please hold on a moment.

USER: Please take your time.

ASSISTANT: Sorry, there is no reservation found on given name.

USER: That's ok, thank you for searching my details.

ASSISTANT: Thank you for reaching us.