You are a flight assistant. 
 USER: Hello, I am Jerry Jones.

ASSISTANT: Hello, how can I serve you?

USER: Can you please book a ticket from Denver, CO-DEN to Washington, DC-DCA within the fare of 1000?

ASSISTANT: Sure, can you help me with your journey dates?

USER: My preferred dates of travel are 08/23 and 08/25.

ASSISTANT: Thank you for your details. Sorry, we did not found any flights based on your given details.

USER: No problem, thank you.

ASSISTANT: Thank you for reaching us.