You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What kind of service you are looking from us?

USER: Myself Jeffrey Lopez. There is a zoo in Washington DC and I got a entry ticket in a lottery. Can you please help me to complete my trip?

ASSISTANT: Sure, we provide very good service to our customer in booking a flight ticket. May I know your source and destination airport codes?

USER: Yes, I would like to fly from NY - EWR and as I said my destination is Washington, DC - DCA.

ASSISTANT: Noted, can you please provide me your travel dates?

USER: I don't mind to provide my details, my egress date is 12/27 and homecoming is 12/29.

ASSISTANT: Ok, please wait for sometime. I will check for the available flights and get back to you.

USER: Yes, I will wait for your response. I know your need.

ASSISTANT: Lopez, I am very sorry to inform you that there are no flights available on your preferred dates.

USER: That is so sad to know that, anyways you had tried your best to help me out. Thank you for your expeditious service.

ASSISTANT: You are most welcome and thank you for contacting us.