You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you today?

USER: I am Jeffery Hernandez. I want to fly to DC with the direct flight to attend a client meeting, can you help me in booking?

ASSISTANT: Sure, may I know your source and destination airport codes?

USER: My boarding and landing airport codes are DFW and IAD.

ASSISTANT: Can you please let me know your travel dates?

USER: I need to depart on Mar 19th and my return date will be on Mar 21st.

ASSISTANT: Do you have any other preferences?

USER: I need to depart in the afternoon.

ASSISTANT: Please let me know your class preference.

USER: I don't have any class preference.

ASSISTANT: Ok, please wait for couple of minutes.

USER: Sure.

ASSISTANT: Sorry, there were no flights found with your preferences.

USER: No issues, I'll choose any alternative to reach my destination. Thank you for your information.

ASSISTANT: Thank you for approaching us.