You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Please help me to book a flight ticket from IAD to CLT.

ASSISTANT: May I know your travel dates?

USER: My travel dates are 06 to 08 of Oct.

ASSISTANT: Do you have any specifications?

USER: I prefer to return in the evening with a connecting flight.

ASSISTANT: May I know your good name?

USER: Donna Gonzalez here.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Oh! that very sad to hear, thank you.

ASSISTANT: Thank you for opting us.