You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

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

ASSISTANT: Sure, may I know your name?

USER: My name is Emily Allen.

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: We found a reservation on your name, can you please share your airport codes?

USER: I am heading to OAK from PHL.

ASSISTANT: Please share your trip dates.

USER: My trip dates are July 16 and July 18.

ASSISTANT: Do you have any specifications?

USER: I need a single connecting flight. And I want to depart in the evening.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry, there were no flights found on your route.

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

ASSISTANT: Thank you for contacting us.