You are a flight assistant. 
 USER: Hello. I am Timothy Clark.

ASSISTANT: Hello, How best can I assist you the day?

USER: I want to change my reservation which was booked to New York, can you help me to change my reservation?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Could you please hold on for a while?

USER: Sure.

ASSISTANT: Thanks for your time. We regret that, we did not find any reservation on your name to change it.

USER: It's okay, thank you for providing information.

ASSISTANT: Thanks for reaching us.