You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you for he day?

USER: I want to change my recent booking due to change of trip, can you help me?

ASSISTANT: Ok, may I know your name please?

USER: I am Brian Lewis.

ASSISTANT: Please wait for a moment Brian Lewis.

USER: Sure.

ASSISTANT: There is no reservation found by the name of Brian Lewis, sorry for the inconvenience.

USER: That's fine, no issues with that one.

ASSISTANT: Have a great day.

USER: Thank you for your help.