You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to go to Houston in this month so could you please help me in flight ticket booking process from DFW to HOU?

ASSISTANT: Sure, I am glad to help you. Please let me know your travel dates.

USER: Thank you for your positive response, I want to departure on Jan 06 and book my return ticket also on Jan 08.

ASSISTANT: Ok, please let me know your specifications.

USER: I want to travel in business class flight so please check with this details.

ASSISTANT: Do you have any other preferences?

USER: No.

ASSISTANT: May I know your name?

USER: Sure, my name is Christopher Gonzalez.

ASSISTANT: Christopher Gonzalez, there is no flight available as per your requirements.

USER: It's ok no problem. Thank you for your service.

ASSISTANT: You are welcome and thank you for choosing us.