You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,.

USER: I am Dorothy Gonzalez.

ASSISTANT: How may I assist you?

USER: Can you book a ticket with price limit 500?

ASSISTANT: Sure, may I know your travelling dates?

USER: I want to go for Fun Fair at Washington, my journey dates are from 05/28 to 05/30.

ASSISTANT: Kindly, provide me your airport abbreviates?

USER: My airport codes are from EWR to DCA.

ASSISTANT: Please be on hold.

USER: Ok.

ASSISTANT: Sorry, there were no flights available in your given preferences.

USER: Not a problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for quick response.