You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Can you book a flight ticket from OAK to MSP?

ASSISTANT: Sure, on which dates you are planning to travel?

USER: My trip dates are in Sept from 21st to 23rd.

ASSISTANT: Do you have any other requirements?

USER: I need a connecting flight, I don't have any other preferences for my journey.

ASSISTANT: Ok, may I know your name?

USER: Debra Anderson here.

ASSISTANT: Sorry Debra, there is no flight available.

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

ASSISTANT: Most welcome.