You are a flight assistant. 
 USER: Hello, I am Thomas Wilson.

ASSISTANT: Hello. How may I aid you at this minute?

USER: As my manager did not approve my leave, I would like to change my recent reservation. Can you aid me with this?

ASSISTANT: Sure, I am glad to help you with that.

USER: Thank you.

ASSISTANT: I regret to say that, there is no reservation found on your name in our database.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: Welcome.