You are a flight assistant. 
 USER: Hello. I am Emma Collins.

ASSISTANT: Hello, how may I help you today?

USER: Please help me to book a flight ticket from AUS to PHX.

ASSISTANT: Sure Emma, can you please share me with your dates of journey?

USER: My preferable travel dates are 06/21 and 06/23.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry Emma, there is no flight found as per your travelling details.

USER: Ok, not an issues. Thank you.

ASSISTANT: You are welcome.