You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Jack Rodriguez. Please book me a ticket from ORD to IAD to meet my family.

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: I have planned to travel on May 19th and return on May 21st.

ASSISTANT: Do you have any class preferences?

USER: I am ok with any class.

ASSISTANT: Do you have any airline preferences?

USER: No.

ASSISTANT: Do you have any other requirements that you are looking for?

USER: I would like to return at afternoon time and I prefer direct flight.

ASSISTANT: Sorry, there are no flights available at your request.

USER: Ok, no problem. Thank you.

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