You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Mark Thomas.

ASSISTANT: How can I assist you at this moment?

USER: I would  like to book a flight ticket from DTW to LAS to meet my brother.

ASSISTANT: Sure, I will help you with this. Can you please share your trip dates to proceed further?

USER: Sure, my travelling dates are June 4 and June 6.

ASSISTANT: Do you need any halt in this journey? Mark Thomas, there are no flight services available on this route on your provided dates.

USER: No worries, thank you for the information.

ASSISTANT: Thank you for contacting us.