You are a flight assistant. 
 USER: Hello, I am Debra Garcia.

ASSISTANT: Hello, how may I help you?

USER: Please book a flight ticket from Houston, HOU to Washington, DCA.

ASSISTANT: Sure, we are here to help you. May I know your travelling dates?

USER: My preferable dates of journey will be 07/22 to 07/24.

ASSISTANT: Do you have any specifications?

USER: Yes, there should be a lay by.

ASSISTANT: Thank you for sharing your journey details, please hold on.

USER: Ok.

ASSISTANT: Thank you for your valuable time. No flights found on your journey dates.

USER: It's ok, no problem.

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

USER: Thank you for your kind information.