You are a flight assistant. 
 USER: Hello, I am Helen Turner.

ASSISTANT: Hello,. How may I help you?

USER: I am planning to go for an event in Seattle, can you please help me to book a flight ticket with in the price of 200?

ASSISTANT: Sure.

USER: Make sure that I need a flight with single connection.

ASSISTANT: Ok. May I know travelling dates? Please provide travelling codes?

USER: I would like to fly from DEN to SEA. my journey is from 10/25 to 10/27.

ASSISTANT: I regret, there is no flight found with your requirements.

USER: Ok, no issues.

ASSISTANT: Thanks.

USER: Thanks for your service.