You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you please book a flight ticket from HOU to EWR?

ASSISTANT: Ok, please provide your trip dates.

USER: Thank you. I have planned my travel dates as May 14 and May 16.

ASSISTANT: Do you have any other requirements?

USER: I would like to return in afternoon time so please check with that.

ASSISTANT: Ok, please wait a minute.

USER: Sure, take your time.

ASSISTANT: May I know your name please?

USER: Sure, myself Margaret Parker.

ASSISTANT: Sorry, we regret to inform you that there is no flight available as per your request.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Most welcome.