You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I am Shirley Baker from Washington. I have to go to Dallas in this month so can you please help me in flight ticket booking process from IAD to DFW?

ASSISTANT: Sure, can you please mention with your dates of travel?

USER: Thank you, I want to take off on May 19 and please confirm my return ticket also on May 21.

ASSISTANT: Please wait for a moment.

USER: Ok, I want a business class airline so please check with this.

ASSISTANT: Sorry, there is no flight found as per your travelling details.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: You are welcome.