You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I am Donna Wilson. I am planning to visit Lake Merritt at Oakland, could you please help me with booking a flight ticket from DCA to OAK?

ASSISTANT: Sure, please share me your planned journey dates?

USER: I would like to depart on Dec 12th and return on Dec 14th.

ASSISTANT: May I know your connection limit?

USER: I need a connecting flight.

ASSISTANT: Please share me your depart and return flight timing?

USER: Make sure that my return time must be evening.

ASSISTANT: Do you have any there requirement related to booking?

USER: No.

ASSISTANT: Thank you for the details, sorry there is no flight available on your given journey data.

USER: Ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Thank you for reaching us, we hope see you again.