You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, is there any help required from my side?

USER: Barbara Perez here. I am event organiser and there is a marriage event in OAK, so I need to travel there, can you help in searching a flight from LAS?

ASSISTANT: Yes, what are your planning dates?

USER: From 12/21 to 12/23.

ASSISTANT: Adams, there is no flights available on your dates to your landing region.

USER: It's fine. Thank you.

ASSISTANT: You are welcome and thank you for reaching us.