You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you today?

USER: I want to change my existing reservation as my exam got postponed. Can you help me out?

ASSISTANT: Sure, I am here to help you. Can I have your name to trace your details?

USER: My name is Sandra Nelson.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: Thank you for waiting, no reservation was found on your good name.

USER: Ok,No issues. Thank you.

ASSISTANT: Thank you for availing us.