You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Brian Walker here.

ASSISTANT: How can I help you?

USER: Reserve a flight ticket for me that is from DTW to DFW. For my business trip to Dallas. My price limit is less than 500.

ASSISTANT: Sure, may I know on what dates you need booking?

USER: My travelling dates for journey are 12/09 to 12/11. I need a connecting flight.

ASSISTANT: Sorry, all flight tickets are sold out.

USER: Ok, I will find out with other airlines. Thank you.

ASSISTANT: Thank you for consulting us, have a great day.