You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you?

USER: I am Nicholas Smith. I am planning to meet my cousin at Minneapolis, MSP. Can you please book a ticket for me?

ASSISTANT: Sure, May I know the source code?

USER: Source code is Washington, DCA.

ASSISTANT: Please help me with your travel dates.

USER: My planned dates are 10/26 to 10/28.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: No problem. Thank you.

ASSISTANT: Thank you for availing us.