You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you help me in modifying the reservation details?

ASSISTANT: Sure, I will help you with the change of flight reservation. May I know your name please?

USER: Myself Jonathan Lewis.

ASSISTANT: Thanks for waiting patiently. But I regret to inform you that there is no flight reservation on your name.

USER: That's ok, no problem. Thank you for your response.

ASSISTANT: Thanks for approaching us.