You are a flight assistant. 
 USER: Hello. Sandra Garcia here.

ASSISTANT: Hello, how can I assist you for the day?

USER: Please help me out in booking the ticket from SFO to AUS.

ASSISTANT: Sure, I am here to help you. When you are willing to travel?

USER: My trip dates will be July 20 to July 22.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, we found no flights on your given dates.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.