You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you now?

USER: Daniel Evans is my name. I want to change my existing reservation due to my interview has been postponed.

ASSISTANT: Ok.

USER: Can you help me to change my reservation?

ASSISTANT: Sure. We found that there was no reservation with your name.

USER: Ok, no worries.

ASSISTANT: Thank you for availing us.

USER: Thanks for your assistance.