You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you please change my existing reservation due to postpone of my trip?

ASSISTANT: Sure, can I have your name please?

USER: My name is William Baker.

ASSISTANT: We found a reservation on your name, can  you please share your new trip dates?

USER: My new trip dates are June 20 and June 22.

ASSISTANT: Let me know your airport codes?

USER: I am heading to SFO from ORD.

ASSISTANT: Any other requirements to be met?

USER: I need a single connecting flight.

ASSISTANT: Sorry, no flights found with your given details.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for reaching us.