You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Jason Campbell.

ASSISTANT: How may I assist you now?

USER: I have to reserve a flight ticket to reach Washington city because I have a business there. So, I need to go there. Can you please help me with ticket booking?

ASSISTANT: Jason Campbell, may I know your desired dates for the following journey to check with availability?

USER: Ok, I am looking to book a ticket on the dates of 06/13 and 06/15.

ASSISTANT: What are your origin and destination airport codes?

USER: The origin and destination airport codes are CLT and IAD.

ASSISTANT: Ok, please wait for a while.

USER: Sure, I can wait for your reply. I need a direct flight for this journey, so please search the best flight for me.

ASSISTANT: Sorry, there are no flights are available for your journey.

USER: Oh! Not a problem with that. I will choose some other source to travel to Washington. Anyways thank you so much.

ASSISTANT: Thank you for consulting with our agency regarding your help.

USER: You are welcome.

ASSISTANT: Have a nice day.