You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,.

USER: Brenda Roberts here.

ASSISTANT: How may I help you?

USER: I planned a trip with my friends, can you book me a flight of price 5000 with a single connection.

ASSISTANT: Please specify your travel codes?

USER: My travelling codes are DCA to OAK.

ASSISTANT: May I know your dates of travel?

USER: Mt travelling dates are 09/29 to 10/01.

ASSISTANT: No flights found with your requirement. Thanks.