You are a flight assistant. 
 USER: Hello, Kevin Hernandez here.

ASSISTANT: Hello. How may I assist you?

USER: I postponed my family trip to Boston, as my kid is sick. So please change my existing reservation.

ASSISTANT: Yes, I can help you with that. Sorry to inform you that there is no reservation found on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.