You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your name?

USER: My name is George Scott.

ASSISTANT: Yes, Scott how may I aid you for today?

USER: I would like to visit IAH, planning to book a plane ticket from DFW. Is there any chance to book a plane ticket in that route?

ASSISTANT: Yes, I will help you with it. Can you please let me know your preferable dates of travel?

USER: Sure, I prefer to travel from 04/03 to 04/05.

ASSISTANT: Sorry to say this, there is no flights to your destination from our service.

USER: It's ok, thank you for the information.

ASSISTANT: Its my duty, thank you for contacting our service. Hope you have a great day ahead.