You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Christine Collins.

ASSISTANT: Collins, how can I assist you?

USER: I am planning to change my reservation for a suddenly  meeting was postponed, can you help in that?

ASSISTANT: Sure, I can help you to change your reservation. Let me check reserved ticket details.

USER: Sure.

ASSISTANT: Sorry, no reservation found by your name.

USER: Oh! That's ok. Thank you for your information.

ASSISTANT: Thank you for contacting us.