You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Can you please book a flight ticket from SFO to DTW?

ASSISTANT: Sure, I am glad to help you. May I know your travelling dates?

USER: My trip dates are Oct 18 and Oct 20.

ASSISTANT: Is there any class preferences?

USER: I am comfortable with any class.

ASSISTANT: Can you please share your airline preferences?

USER: I prefer to travel in normal cost airlines.

ASSISTANT: May I know your connection limit?

USER: I need a stopover in between my journey.

ASSISTANT: Do you have any specifications?

USER: No.

ASSISTANT: May I know your name?

USER: I am William Gonzalez.

ASSISTANT: Sorry, there are no flights found on your trip dates.

USER: Ok, not a problem. Thank you for your information.