You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I get off to you?

USER: I would like to change my reservation due to change in my trip, please help me with it.

ASSISTANT: Sure, May I know your name to check the status and revert you.

USER: My name is Timothy Clark.

ASSISTANT: There is no reservation found by the name you provided.

USER: Thank you for the information.

ASSISTANT: Thank you for choosing us.