You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how can I help you?

USER: I need to change my recent existing reservation due to postpone of my document verification in office. Can you please help me in changing my reservation?

ASSISTANT: Sure, may I know your name to check the database and revert you.

USER: My name is Raymond Phillips.

ASSISTANT: We could not find any reservation by this name in the reservation list.

USER: No problem, thank you.

ASSISTANT: Thank you for picking us.