You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I am Margaret Wilson. Can you please help me in booking a flight ticket within fare of 1000 from Denver, DEN?

ASSISTANT: Sure, may I know your source and destination airport codes?

USER: My destination airport code is Atlanta, ATL.

ASSISTANT: When would you like to travel?

USER: My travelling dates are from 07/08 to 07/10.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, no flights are available with your request.

USER: Ok, no worries. Thank you.

ASSISTANT: Thanks for availing us.