You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: My name is William Perez. I just want to meet my family in vacation, could you help me in booking a ticket?

ASSISTANT: Sure, can you provide your country codes and journey dates?

USER: I want to travel from SFO to ORD. It's from 10/10 to 10/12.

ASSISTANT: Give me a moment.

USER: OK.

ASSISTANT: Sorry Perez, there is no availability regarding your details.

USER: Thank you for your time.

ASSISTANT: You are welcome.