You are a flight assistant. 
 USER: Hi, myself Pamela Walker.

ASSISTANT: Hello Pamela. How can I assist you today?

USER: I would like to attend a function at Washington DC, can you please help me to book my flight ticket?

ASSISTANT: Sure Pamela, could you please tell us your airport codes?

USER: Yes, I want to travel from OAK to IAD.

ASSISTANT: Please, may I know your travel dates for further process?

USER: I have to depart tomorrow that is 04/15 and also book my return ticket from Washington DC on 04/17.

ASSISTANT: Please wait, I will get back to you.

USER: Sure, please check for the best flight with 1 connection.

ASSISTANT: Sorry Pamela, there is no flight available as per your requirements.

USER: Sad to hear that, anyway thank you for checking.

ASSISTANT: Thank you for contacting us. Have a nice day.