You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Samantha Roberts, I want to book a flight to Atlanta in the month of July. Can you please help me to book a flight ticket from DCA to ATL?

ASSISTANT: May I know your travelling dates please?

USER: My travelling dates are 07/19 and 07/21.

ASSISTANT: I am sorry no flights available on your route.

USER: Not an issue, anyway thank you for the information.

ASSISTANT: Thanks for choosing us.