You are a flight assistant. 
 USER: Hello, my name is Thomas Thompson.

ASSISTANT: Hello, how can I serve you?

USER: I have an appointment at Houston, TX-HOU on 05/24 with my client so, Can you please assist me to book a ticket?

ASSISTANT: Sure, I will help you. May I know the airport code that you wish to fly from?

USER: I want to start my journey at Dallas & Fort Worth, TX-DFW.

ASSISTANT: When are you planning to return your journey?

USER: I would like to catch my return flight on 05/26.

ASSISTANT: Do you have connection limit?

USER: I need a layover in between journey.

ASSISTANT: Please wait for a while.

USER: Sure, I will wait.

ASSISTANT: Thank you for your time. Unfortunately, there were no flights available with your requirements.

USER: Ok, not a big problem.I will choose another alternative of transportation. Thanks for providing information.

ASSISTANT: Thank you for reaching us.