You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I address you?

USER: I am Carol Davis. Can you please change my existing reservation as my plan to meet my childhood friend got postponed?

ASSISTANT: Sure, please give me a minute.

USER: Sure, take your time.

ASSISTANT: Thanks for your valuable time, there is no reservation found with your name in our database.

USER: It's ok, no problem.

ASSISTANT: Thanks for availing us.

USER: Thank you for your response.