You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Donna Taylor here.

ASSISTANT: How can I assist you?

USER: Can you please help me in booking a flight ticket from LAS to DCA?

ASSISTANT: Sure, I will help you. Can you please provide your planned journey dates?

USER: Sure, my travel dates are from July 11 to July 13.

ASSISTANT: Let me know your connection limit.

USER: I need a connecting flight.

ASSISTANT: Which class would you prefer for your journey?

USER: I am comfortable with any class.

ASSISTANT: Do you have any airline preference?

USER: No.

ASSISTANT: May I know, at what time you are planning to depart and arrive?

USER: I would like to depart in the afternoon.

ASSISTANT: Give me a minute, I will let you know the flight availability.

USER: Sure, take your time.

ASSISTANT: Thank you for your time, there were no flights available that matches with your requirements.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for approaching us.