You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Gary Walker. Owning to an emergency I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Please give me a moment.

USER: Sure.

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

USER: Ok, no problem.

ASSISTANT: Thank you.

USER: Thank you for the information.