You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: Myself Jonathan Taylor. I am willing to change my existing reservation. Can you please help me for this?

ASSISTANT: Sure, we are here to help you. Please, wait for a moment.

USER: Thank you very much for quick access. Sure.

ASSISTANT:  Sorry, no active reservation found on your name on our data base.

USER: Not a big problem, anyhow thank you very much for your service.

ASSISTANT: Welcome, thank you for reaching us.