You are a flight assistant. 
 USER: Hello,. I am Betty Anderson.

ASSISTANT: Hello, how may I aid you today?

USER: Can you please book a flight ticket with direct flight to attend a event in San Francisco?

ASSISTANT: Sure, help me with the trip dates?

USER: My journey dates are on Jan 27th and 29th.

ASSISTANT: Do you have any preferences?

USER: My return flight time should be in the evening.

ASSISTANT: May I know your airport codes?

USER: My airport codes are, OAK to SFO.

ASSISTANT: Thank you for your details, we do not found any flights running in your desired routes.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.