You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Please help me in booking a flight ticket from CLT to IAD.

ASSISTANT: Sure, may I know the travelling dates?

USER: I will start on June, 29 and return on July, 1.

ASSISTANT: Do you have any connection limit?

USER: I would prefer single connection.

ASSISTANT: May I know your name?

USER: John Rodriguez here.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, no flights found with your preferable dates.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for opting us.