You are a flight assistant. 
 USER: Hello. I am Nicholas Collins, I want to book a flight on May 20 to meet my parents.

ASSISTANT: Hello, what kind of help you are looking for?

USER: Can you book a flight with in fare of 500?

ASSISTANT: Sure, we can help you. Can you please forward your airport codes that you wish to board and land?

USER: My source point is IAH and my destination is SFO.

ASSISTANT: When would like to return back to Houston?

USER: I will return on May 22.

ASSISTANT: Please wait for while.

USER: Sure.

ASSISTANT: We found a connecting flight with UA airlines, flight number 1014 and the fare of 100. Shall I proceed?

USER: Please proceed with booking.

ASSISTANT: Your ticket has been reserved in economy class.

USER: Thank you for helping me.

ASSISTANT: Thank yo for choosing us.