You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: I am planning to visit Redwood regional park which is one of the famous attraction in Oakland, OAK. Can you avail me to book a direct flight?

ASSISTANT: Sure, I am here to help you in reservation.

USER: Thank you.

ASSISTANT: May I know your source and destination airports codes please?

USER: My source is from Detroit, DTW.

ASSISTANT: Ok, may I know your travelling dates please?

USER: My travelling dates are June 26 and 28.

ASSISTANT: Ok, may I know your connection limit please?

USER: I need a direct flight.

ASSISTANT: Ok, may I know your class preference please?

USER: I prefer economy class.

ASSISTANT: Do you have any other specifications please?

USER: No.

ASSISTANT: May I know your good name please?

USER: Rebecca Martinez here.

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

USER: Ok, thank you.

ASSISTANT: Thank you for opting us.