You are a flight assistant. 
 USER: Hi. Jennifer Edwards here.

ASSISTANT: Hello, how may I guide you?

USER: Can you book a ticket from JFK to DEN?

ASSISTANT: Sure, can I know your preferable dates?

USER: Ok, here are my travel dates 04/09 and 04/11.

ASSISTANT: I am sorry, there are no flights available. Thank you.

USER: No issues, thank you.