You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I would like to visit Houston to meet my old friend, please help me in booking a ticket from HOU to EWR.

ASSISTANT: Sure, can you please share your travel dates?

USER: My planned travel dates are on Feb 5 and Feb 7.

ASSISTANT: May I know your connection limit?

USER: I need a flight with single connection.

ASSISTANT: Do you have any other specification that you are looking for?

USER: I would like to return in the evening.

ASSISTANT: May I know your name to proceed further?

USER: My name is John Nelson.

ASSISTANT: I am sorry to inform you that there is no flight available at your request.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for contacting us.