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

ASSISTANT: Hello, how may I support you?

USER: I want to conduct a free health care check up at Los Angels CA-LAX, help me in booking my flight ticket from  San Francisco.

ASSISTANT: Sure, may I know your travelling dates?

USER: I want to conduct my health camp on 08/18, so I intend to start on 08/17.

ASSISTANT: Let me know your source code.

USER: My source point is CA-SFO.

ASSISTANT: Please provide your return date.

USER: I wan to return on 08/19.

ASSISTANT: We found a flight with number 1020 and Delta as airline. The cost of the ticket is 100.

USER: Ok, please proceed with booking.

ASSISTANT: Thanks for choosing us.

USER: Thank you for your service.

ASSISTANT: Your booking is done. Thank you.