You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Carolyn Harris.

ASSISTANT: What can I do in your service today?

USER: I would like to book a plane ticket from JFK to LAS, will you reserve a seat for me in any airline?

ASSISTANT: Ok, please mention your travelling dates on which you would like o travel?

USER: Sure, I am planning to travel from 06/20 to 06/22.

ASSISTANT: Ok, give me a moment to check for the availability for you.

USER: Ok.

ASSISTANT: Sorry to inform you Carolyn, no flights are available on your requested dates.

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

ASSISTANT: Thank you for reaching our assistance. Have a nice day.