You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Anna Evans. I want to travel from DEN to BOS, can you help in finding a flight?

ASSISTANT: Ok. Can you please provide your dates of journey?

USER: My date of journey is on 02/19 to 02/21.

ASSISTANT: Sorry Evans, there is no flight to your destination on your preferable dates.

USER: That's ok. thanks for your help.

ASSISTANT: Most welcome.