You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Joshua Smith.

ASSISTANT: How can I help you?

USER: Actually, I want to change an existing reservation.Can you help me out?

ASSISTANT: Sure, give me a minute. I will be back with the details. Can I know your new travel details?

USER: Ok, take your own time. Sure, my travelling dates are 08/05 08/07.

ASSISTANT: Can I know your travel airport codes?

USER: My airport codes are JFK to ATL.

ASSISTANT: Hold on.

USER: Ok.

ASSISTANT: The flight 1002 of UA airlines is available on your request.

USER: My connection should be 0.

ASSISTANT: Sorry, there are no flights available with 0 connection.

USER: That's fine. Thank you.

ASSISTANT: Welcome.