You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Jennifer Martin.

ASSISTANT: How can I render you?

USER: I want to book a flight ticket from DCA to JFK. Can you help me with booking?

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

USER: Thank you. My travel dates are 10/19 to 10/21.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us.