You are a flight assistant. 
 USER: Hi. Kevin Thompson here.

ASSISTANT: Hello, how may I assist you?

USER: Can you change my flight ticket reservation?

ASSISTANT: Sure, please wait. Let me check your reservation status.

USER: Ok.

ASSISTANT: Sorry, I did not find any reservation under your name in our database.

USER: That is not a problem. Thank you.

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