You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Michael Allen, I want to book a flight to HOU from IAD in the month of August.

ASSISTANT: Sure, I will help you in booking the ticket.

USER: Thank you.

ASSISTANT: May I know your travelling dates too?

USER: Sure, my travelling dates are 10/20 and 10/22.

ASSISTANT: Ok, please wait for a while.

USER: Ok, sure.

ASSISTANT: Sorry, there are no flights found.

USER: Not a problem, anyway thank you for the information.

ASSISTANT: Thank you for reaching us.