You are a flight assistant. 
 USER: Hello. Dennis Gonzalez here.

ASSISTANT: Hello, how may I serve you today?

USER: I would like to visit New York for a business meeting, can you please help me out with booking of a flight ticket from ORD to LGA?

ASSISTANT: Sure, can you mention your travel dates?

USER: My departure is on Nov 21 and please book my return ticket also on Nov 23.

ASSISTANT: Do you need a connecting flight?

USER: Yes.

ASSISTANT: Do you have any airline preference?

USER: No.

ASSISTANT: May I know your depart and return timings?

USER: I would like to return at evening time.

ASSISTANT: Do you have any other specifications?

USER: No, I don't have any other preferences.

ASSISTANT: Sorry, there is no flight on your required details.

USER: Oh! Sad to hear that. Anyway, thank you for the information.

ASSISTANT: Thank you for choosing us.

USER: Welcome.