You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Can you book a connecting flight to Las Vegas?

ASSISTANT: Sure, may I know when are you travelling?

USER: I intend to start on 04/20 and end on 04/22.

ASSISTANT: Ok, can you provide your airport codes?

USER: My journey is from LGA to LAS.

ASSISTANT: Ok, please hold on I will check the availability and get back to you.

USER: Sure.

ASSISTANT: Thanks for your time. There are no flight available at this moment.

USER: Ok. Thank you for your service.

ASSISTANT: Thank you for reaching us. May I know your name?

USER: I am Timothy Miller.

ASSISTANT: Thank you.