You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am David Allen.

ASSISTANT: How may I help you?

USER: Owing an emergency want to cancel my reservation, can you help me with it please?

ASSISTANT: Sure, I am ready to help you.

USER: Thank you.

ASSISTANT: Sorry, there are no reservation found on your name.

USER: That's ok, thank you for the response.

ASSISTANT: Thank you for reaching us.