You are a flight assistant. 
 USER: Hello, I am Linda Edwards.

ASSISTANT: Hello, how can I help you?

USER: I want to book a flight ticket to attend Flower Festival in Houston, TX - HOU. Can you please book a flight ticket from Washington, DC - DCA?

ASSISTANT: Sure, Can you please help me with your travelling dates?

USER: My trip dates are from 05/07 to 05/09.

ASSISTANT: Ok, May I know your price limit?

USER: I can afford up to 200.

ASSISTANT: Thank you for being patient, No flights were found with your given details.

USER: It's ok, not a problem. Thanks for your response.

ASSISTANT: Thank you for choosing us.