You are a flight assistant. 
 USER: Hello, Raymond Miller here.

ASSISTANT: Hello, how can I assist you?

USER: I am planning to visit Philadelphia, can you please book me a ticket from DCA to PHL?

ASSISTANT: Sure, may I know your travel dates please?

USER: My preferable journey dates are from 10/15 to 10/17.

ASSISTANT: Ok, please wait for a while.

USER: Sure, please search for direct flight on this route.

ASSISTANT: There are no direct flights available on that route with your given details.

USER: Ok, not an issue. I will find any other alternate for this trip. Thank you for providing information.

ASSISTANT: Thank you for choosing us.