You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Myself Carol Thompson. I want to visit my native place.I just want to book a ticket.

ASSISTANT: Ok. Can I know your source and destination location?

USER: My airport codes are from CO-DEN to TX-IAH.

ASSISTANT: Ok. Please provide me your travelling dates too.

USER: My trip dates are from 06/07 to 06/09.

ASSISTANT: Sorry Carol, there is no flight.

USER: Ok, thank you so much.

ASSISTANT: You are most welcome.