You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, I am glad to help you. Please provide your good name?

USER: Myself Amy Collins.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Thank you for waiting, we found a reservation on your name, please share your travelling dates.

USER: I want to fly on Sept 30 and return on Oct 02.

ASSISTANT: Can I know your airport codes?

USER: My airport codes are LGA, DCA.

ASSISTANT: Do you need a connecting flight?

USER: I need a single connection.

ASSISTANT: Do you have any other specifications?

USER: I don't have any other specifications.

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

USER: Not an issue. Thank you.

ASSISTANT: Thank you for availing with us.