You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: I would like to change my existing reservation which was made on the name of John Moore. Can you help me with it?

ASSISTANT: Sure, please hold for a moment.

USER: Ok.

ASSISTANT: We are happy to inform you that we found a reservation on your name. Please share your new journey dates?

USER: They are rescheduled on 10/10 and 10/12.

ASSISTANT: Let me know your boarding point and landing point?

USER: My source is DCA and destination is SEA. I need a direct flight.

ASSISTANT: Thank you for sharing your details, there are no flights found with the given details.

USER: Ok, thank you.

ASSISTANT: Thank you.