You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I would like to book a ticket from LGA to SFO, can you please help me out?

ASSISTANT: Your travelling dates please?

USER: I am travelling on these dates April 19th and 21st.

ASSISTANT: May I know your connection limit please?

USER: I need single connected flight.

ASSISTANT: Do you have any other specifications?

USER: I don't have any other preferences.

ASSISTANT: May I know your name please?

USER: Matthew Young here.

ASSISTANT: I am sorry no flights found on your route.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for choosing us.