You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Catherine Taylor here.

ASSISTANT: How may I help you today?

USER: I want to travel from LAS to JFK for my business meeting, can you please check is there any flight available between those locations?

ASSISTANT: Sure, may I now your travelling dates, please?

USER: Ok, my departure is on Apr 23 and please book my return ticket also on Apr 25.

ASSISTANT: Please wait a moment.

USER: Sure but please book my return flight at the time of evening.

ASSISTANT: Sorry, no flight tickets are available in the evening.

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

ASSISTANT: Thank you for reaching our service.

USER: Welcome.