You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am planning to visit Houston, can you please book me a ticket from DEN to IAH?

ASSISTANT: Sure, can you provide me with the itinerary travel dates.

USER: My preferable journey dates are Oct 11 and Oct 13.

ASSISTANT: Is there any class preference?

USER: No.

ASSISTANT: May I know if there are any airline preferences?

USER: I am comfort with any airlines.

ASSISTANT: Is there any time concern?

USER: I prefer to return in morning flight.

ASSISTANT: May I know the connection limit?

USER: I am ok with any flight.

ASSISTANT: May I know your name please?

USER: My name is Ryan Thomas.

ASSISTANT: Give me a moment.

USER: Sure.

ASSISTANT: Sorry to inform that there are no flights on your route.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for reaching us.