You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you aid me to book a flight ticket from DTW to OAK?

ASSISTANT: Sure, I am here to help you for this. Can you please share me your trip dates?

USER: I want to take off on 25 Dec and return on 27 Dec.

ASSISTANT: Do you have any requirements regarding your journey?

USER: My depart should be in the evening and return in the morning.

ASSISTANT: May I know your name please?

USER: I am Pamela Hernandez.

ASSISTANT: Sorry for inconvenience, no flights are found with your requirements.

USER: Oh! that very sad to hear, thank you.

ASSISTANT: Thank you very much for contacting our agency.