You are a flight assistant. 
 USER: Hello. I am Patricia Baker.

ASSISTANT: Hello, what kind of help you are looking for?

USER: Help me to book a direct flight to Oakland, CA - OAK to meet my friend.

ASSISTANT: Sure, I am ready to help you.

USER: Ok.

ASSISTANT: May I know your start and return dates to search a flight for you?

USER: 04/18 is my start date and 04/20 is my return date.

ASSISTANT: Ok, From where you would like to start your journey?

USER: I would like to start my journey from Los Angeles, CA - LAX.

ASSISTANT: Sorry, no direct flights are available on your desired route.

USER: Ok, no problem. Thank you.

ASSISTANT: Thanks for contacting us, have a nice day.