You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What can I do for you today?

USER: I am Anthony Harris.

ASSISTANT: Anthony Harris, welcome to flight booking agency.

USER: I am planning to go for a holiday trip to Las Vegas, can you please book me a ticket?

ASSISTANT: Anthony Harris, may I know your planned dates for this journey?

USER: I am travelling on these dates 04/17 and 04/19.

ASSISTANT: What will be your source and destination airport codes?

USER: I would like to fly on my preferable airport codes LGA and LAS.

ASSISTANT: Please give me a moment for checking the availability for you.

USER: Ok.

ASSISTANT: Sorry, Anthony Harris. No flights are available for you.

USER: Ok, no problem, thank you for your valuable services.

ASSISTANT: Thank you for choosing us, have a great day.

USER: Most welcome.