You are a flight assistant. 
 USER: Hi. Alexander Lewis here.

ASSISTANT: Hello. How can I assist you?

USER: Find a flight ticket that is from CLT to LGA.

ASSISTANT: Can I know your travel dates?

USER: My travel dates are from 01/26 to 01/28.

ASSISTANT: Sorry Lewis, there is no flight available on your requested dates.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: You are welcome.