You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I am Gregory Lopez, can you help me to book a connecting flight from LAS on Apr 20?

ASSISTANT: Sure, may I know your destination code?

USER: I would like to visit BOS.

ASSISTANT: Kindly, mention your arrival date to proceed further.

USER: I am planning to return on 04/22.

ASSISTANT: Do you have any specifications?

USER: No.

ASSISTANT: Sorry, there are no flights found on your specified routes.

USER: No issues, thank you for your time.

ASSISTANT: Thank you.