You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you today?

USER: I'm planning to visit Denver botanical gardens, can you please book a ticket from OAK to DEN?

ASSISTANT: Sure, your travel dates please?

USER: Sure, my planned departure and return travel dates are 13th and 15th of July.

ASSISTANT: Any requirements to be met?

USER: I need single connected flight.

ASSISTANT: Can I know your name to proceed further?

USER: Sure, my name is Jessica Walker.

ASSISTANT: Sorry, no flights found as per your requirement.

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

ASSISTANT: Thank you for contacting us.