You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I am Charles Martinez, can you help me to book a flight from SFO to CLT?

ASSISTANT: Sure, can you please share your travel dates?

USER: Ok,my travel 10/12 and 10/14.

ASSISTANT: Sorry, no flights are available on your route.

USER: Ok, not a problem, thank you for assisting me.

ASSISTANT: Welcome, have a nice day.