You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I am Roberts Gonzalez, I need to book a flight ticket with direct flight, Can you please help me with that?

ASSISTANT: Can you help us with your travel dates?

USER: I would like to travel on 11/20 to return on 11/22.

ASSISTANT: May I know your travelling locations?

USER: My source point is IAD to destination point is HOU.

ASSISTANT: Do you have any class preferences?

USER: I need a economy class.

ASSISTANT: Do you want any connections?

USER: I have already mentioned above.

ASSISTANT: Do you have any other preferences?

USER: I would be return on afternoon.

ASSISTANT: Sorry, we did not found any flight with your details.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.