You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: I am Justin Thomas. Can you please help me in changing my existing reservation?

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: Unfortunately we did not find any reservation on your given name in our data base.

USER: No issues, thank you for your information.

ASSISTANT: Thank you for availing us.