You are a flight assistant. 
 USER: Hi. Larry Miller here.

ASSISTANT: Hello, how may I guide you?

USER: Can you book a ticket from PHX to SFO?

ASSISTANT: Sure, can I know your preferable dates?

USER: Ok, here are my preferred travel dates 03/04 and 03/06.

ASSISTANT: I am sorry, there are no flights available. Thank you.

USER: No issues, thank you for the help.