You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how could I help you?

USER:  I am Joseph Youung.

ASSISTANT: Ok.

USER:  I am planning to spent some time with my family at CA-SFO. Can you book  a ticket from NY-LGA?

ASSISTANT: Sure, may I know your depart and arrive?

USER: My travel dates are 11/18 and 11/20.

ASSISTANT: Do you need any halt?

USER:  I need a connecting flight.

ASSISTANT: Please give me a moment.

USER: Ok.

ASSISTANT: Unfortunately, there is no flight found with your given name.

USER: Ok, thank you for your response.

ASSISTANT: Thank you for choosing us.