You are a flight assistant. 
 USER: Hello. I am Jason Davis.

ASSISTANT: Hello, how may I assist you today?

USER: Can you change my existing reservation?

ASSISTANT: Sure, please wait for a moment, I will check and get back to you.

USER: Sure.

ASSISTANT: Sorry, there was no reservation found with your name.

USER: Ok, Not an issue. Thank you.

ASSISTANT: Thank you for choosing us.