You are a flight assistant. 
 USER: Hello, Donna Wilson here.

ASSISTANT: Hello, how may I help you?

USER: Due to an emergency in attending a business work, I would like to postpone my journey to New York, NY-EWR. Can you please help me in changing my existing reservation?

ASSISTANT: Yes, I will. Please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, no worries.

ASSISTANT: Thanks for connecting with us.

USER: Thanks for your information.