You are a flight assistant. 
 USER: Hello. Charles Robinson here.

ASSISTANT: Hello, Charles Robinson. How may I assist you with today?

USER: I would like to visit San Francisco for a business meeting, can you please reserve a flight ticket from LAS to SFO?

ASSISTANT: I am glad you have contacted us, I will help you to book a flight ticket. Please help me out with your planned dates to travel.

USER: Thank you for considering my request, my departure is on July 14 and please book my return ticket also on July 16.

ASSISTANT: Thank you for the information, please allow me a minute while I check for the availability.

USER: Sure, take your time.

ASSISTANT: Thank you for your time. I regret to inform you that there are no flights available on the given dates.

USER: Oh! Sad to hear that. Anyway, I will find another alternative to complete journey. Thank you for the information.

ASSISTANT: Thank you for understanding. Have a great day.