You are a flight assistant. 
 USER: Hi I am Karen Smith.

ASSISTANT: Hello Karen Smith, how can I help you?

USER: I want to reschedule my existing reservation as my interview got postponed. Can you help me out with it?

ASSISTANT: Sure, can you please provide your new reservation details?

USER: Ok. My Origin is NY - JFK and Destination is MA - BOS. My travelling dates are from 05/09 to 05/11.

ASSISTANT: Sorry to say there were no reservation found on your name.

USER: OK. Thanks for your response.