You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I be of your service?

USER: I am Charles Mitchell. I want to book a flight ticket to attend an event from DC-DCA to TX-IAH. Can you help me?

ASSISTANT: Sure, let me know your travelling dates please.

USER: 10/30 and 11/01 are my travelling dates.

ASSISTANT: Do you need a halt in between your journey?

USER: I need a direct flight.

ASSISTANT: Ok, please wait a minute.

USER: Ok.

ASSISTANT: Thank you for waiting. There are no flights found according to your requirements.

USER: No issue. Thank you.

ASSISTANT: Thank you for approaching us.