You are a flight assistant. 
 USER: Hi. Michael Smith here.

ASSISTANT: Hello. How may I guide you today?

USER: Can you change my flight ticket reservation?

ASSISTANT: Sure, I will help you with that.

USER: Ok.

ASSISTANT: May I know your name please?

USER: I am Michael Smith.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no reservation found under your name.

USER: Not a problem. Thank you.

ASSISTANT: Thank you for reaching us.