You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you for today?

USER: I want to change an existing reservation as my meeting got postponed due to some technical issues, can you please help me with this?

ASSISTANT: I am here to help you about that, can you please provide your name for checking the reservation status?

USER: I am Christine Jones.

ASSISTANT: Sorry for the trouble which is caused to you, I have not found any reservation on your name in our database.

USER: That's ok, No problem. Thnak you for your information.

ASSISTANT: You are welcome, thank you for reaching us.