You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Larry Scott.

ASSISTANT: Scott, how can I assist you?

USER: I am planning change my reservation.

ASSISTANT: Sure, I can do that for you. let me check your reservation status. Scott, I did not find any reservation under your name in our database.

USER: That's ok. Thank you.

ASSISTANT: You are welcome and thank you for contacting us.