You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: David Baker here.

ASSISTANT: Do you need any help from my side?

USER: I am looking for a business class flight for my business trip to Oakland. So can you book a flight ticket for me?

ASSISTANT: Sure, may I know your name for further assistance?

USER: I am David Baker.

ASSISTANT: May I know your airport codes?

USER: The airport codes are from MSP to OAK.

ASSISTANT: May I know your travel dates?

USER: The trip dates are from Mar 11 to Mar 13.

ASSISTANT: May I know your other specifications?

USER: I would like to depart in the morning time.

ASSISTANT: Thank you for your information, I am unable to search for the flight on your travel dates to reserve a flight ticket for your journey.

USER: Did you check with a single connection flight?

ASSISTANT: Yes, I have checked with all your requirements and I have informed you that there is no flight.

USER: Not a problem. Thank you.

ASSISTANT: You are welcome and thank you for reaching us.