You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am David Hill, I want to travel BOS on 06/11. Can you please help me to book a flight ticket?

ASSISTANT: Sure, I will help you. Can you please provide me your travelling dates?

USER: My travelling dates are 06/11 and 06/13.

ASSISTANT: Ok, may I know your source airport code?

USER: My source code is DTW.

ASSISTANT: Ok, give me a moment.

USER: Ok, please take your time.

ASSISTANT: Sorry, there is no flight available for you. Thank you for choosing us.