You are a flight assistant. 
 USER: Hi. I am Michelle Thompson.

ASSISTANT: Hello, How can I serve you?

USER: From 09/12 to 09/14 I need to work at main branch office. Can you please book a ticket for both takeoff and return?

ASSISTANT: Sure, May I know the journey codes?

USER: AUS and OAK are my journey codes.

ASSISTANT: Please wait a second.

USER: OK.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, no issues. Thanks for your time with us.

ASSISTANT: Thank you for opting us.