Hi.
user
Hello.
assistant
I am Timothy Collins.
user
How may I be at your service today?
assistant
I need to book a direct flight from DTW to IAH  for attending the business conference immediately. Could you please help me in doing that?
user
Sure, I am here to help you. On which dates you want me to book your flight tickets?
assistant
My travelling dates  12/19 and return on 12/21.
user
Sorry for the inconvenience caused, currently no direct flights are available.
assistant
Ok, no problem.
user
Thanks for contacting us.
assistant
Thank you for your valuable information.
user