You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Alexander Mitchell. I am planning to visit LAS to meet my father, can you please find a flight from PHL?

ASSISTANT: Ok, may I know your travelling dates?

USER: My planning dates are from 01/21 till 01/23.

ASSISTANT: Sorry, there is no flight is available for you on your route.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, have a nice day.