You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Benjamin Jones here. I would like to book a ticket from CLT to DEN.

ASSISTANT: Sure, I can help you with that. May I know your planned travel dates please?

USER: My itinerary travel dates are as follows Apr 19 and Apr 21.

ASSISTANT: Can I know in which class you prefer to travel?

USER: I have no class preference.

ASSISTANT: Do you any specifications regarding your depart and arrival time?

USER: My return time should be in the evening.

ASSISTANT: Please let me know if you have any other specifications.

USER: I would like to board on single connection flight.

ASSISTANT: Ok, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Sorry, there are no flights available for you on those dates with your given details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us, have a nice day.