You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to book a direct flight from Austin, TX - AUS to Denver, CO - DEN to spend time with my family. Can you help me in finding a flight?

ASSISTANT: Sure, can you please provide your journey dates?

USER: I want to start my trip on 09/30 and return on 10/02.

ASSISTANT: Ok, let me check the availability of flights and revert you.

USER: Ok.

ASSISTANT: Unfortunately, there is no direct flight to Denver.

USER: Ok, no issues. Thanks for your response.