You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am William Collins.

ASSISTANT: Collins, how can I help you today?

USER:  I am planning to visit Disneyland at Seattle, could you please help me with booking a flight ticket?

ASSISTANT: Sure, can you please let us know your airport codes?

USER: Well, I will start from DCA to reach my destination which is SEA.

ASSISTANT: Ok, can you please provide me your trip dates?

USER: My travelling dates are 05/20 to 05/22.

ASSISTANT: Ok, please wait for a moment. I will get back to you.

USER: Sure.

ASSISTANT: I found a flight for you in Hawaiian airlines and the ticket costs you 100 only. Can I book the ticket?

USER: You can reserve it.

ASSISTANT: Your ticket is booked successfully and the flight number is 1018.

USER: Thank you for helping.

ASSISTANT: Thank you for choosing us.