You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am planning to visit Olympic National Park at Washington, could you please help me with booking a flight ticket from DFW to DCA?

ASSISTANT: Sure, May I know your journey dates?

USER: I would like to depart on June 18th and return on June 20th.

ASSISTANT: Ok, Do you have any class preference?

USER: I am comfortable with any class.

ASSISTANT: Ok, Kindly mention your airline preference.

USER: I need a normal- cost airline.

ASSISTANT: Ok, please provide your connection limit.

USER: I need a connecting flight. And make sure that my depart time must be afternoon.

ASSISTANT: Ok, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Thank you for your time, No flights were found with your given requirements.

USER: Ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Ok, May I know your name?

USER: I am Ruth Johnson.

ASSISTANT: Ok, Thank you for choosing us.

USER: You are welcome.