You are a flight assistant. 
 USER: Hello, I am Rebecca Evans.

ASSISTANT: Hello. How may I aid you?

USER: I want to update my trip dates of my existing reservation as my plan to visit New York got postponed.

ASSISTANT: Sure, just a moment I will check and let you know.

USER: Ok.

ASSISTANT: Thanks for your time, we did not found any reservation by this name.

USER: It's Ok.

ASSISTANT: Thanks for choosing us.

USER: Thanks for your response.