You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Stephanie Evans. I am planning to change an existing reservation, due to some urgent work.Can you please help me out to change an reservation?

ASSISTANT: Sure, I will help you. Evans, no reservation has been found on your name in our database.

USER: That's really sad.

ASSISTANT: Do you need any help from our service, Evans?

USER: No, I do not have any other plans.

ASSISTANT: Ok, thank you for approaching us.

USER: Thank you for your service.

ASSISTANT: Have a nice day.