You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you?

USER: Can you please help me to change my details in my existing reservation?

ASSISTANT: Sure, please provide your name for checking purpose.

USER: My ticket was reserved in the name of Helen Adams.

ASSISTANT: Sorry Adams, there is no reservation found in our data base when I checked. Thank you for reaching us.

USER: Ok, fine thank you.

ASSISTANT: Have nice day.