You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Joseph Martin.

ASSISTANT: How may I aid you?

USER: Can you help me in changing my recent reservation, as my interview is rescheduled?

ASSISTANT: Sure, I will help you. Give me  a minute, please.

USER: Ok.

ASSISTANT: Thanks for your valuable time. I did not find any reservation on your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for approaching us.