You are a flight assistant. 
 USER: Hello, myself Robert Campbell.

ASSISTANT: Hello, how may I help you?

USER: I would like to meet my grand parents at Oakland, please help me in booking a ticket from DTW to OAK.

ASSISTANT: Ok, on which dates are you planning your journey?

USER: My trip dates are 03/12 and 03/14.

ASSISTANT: Please wait for a minute.

USER: Sure, take your time.

ASSISTANT: There are no flights available at this moment.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for contacting us.