You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,. How may I assist you?

USER: I want to attend the film festival which is going to held at Washington. So, can you please book me a flight ticket on 07/05?

ASSISTANT: Ok. Please provide your airport codes?

USER: Sure, I would like to travel from NY-EWR to DC-IAD.

ASSISTANT: May I know your return date?

USER: I will come back on 07/07.

ASSISTANT: Please provide flight connections limit?

USER: Sure, I need a single connecting flight.

ASSISTANT: Please let me know your name?

USER: I am Margaret Robinson.

ASSISTANT: No flight found with your requirement.

USER: Ok, no problem.

ASSISTANT: Thanks.

USER: Thank you for your time.

ASSISTANT: Have a nice day!.