You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My event has been postponed and I want to change my reservation, can you help me?

ASSISTANT: Sure, provide your name please.

USER: I am Sarah Jones.

ASSISTANT: There is no reservation with your name Sarah Jones.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for contacting us.