You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Jessica Clark. I need a reservation to meet my project manager. Can you please book a ticket with a price limit of 500?

ASSISTANT: Sure, may I know when you want to travel?

USER: I want to travel on 10/26 and 10/28.

ASSISTANT: Ok, please help me with your airport codes.

USER: My airport codes are from HOU to DCA.

ASSISTANT: Please stand by.

USER: Ok.

ASSISTANT: Thank you for waiting. Sorry to say no flights found with your details.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you.