You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: Please book a ticket to San Francisco, CA-SFO from Washington DC-IAD.

ASSISTANT: Sure, I am ready to help you with that. Can I have your travel dates please?

USER: Depart is by 03/22 and 03/24 is return date.

ASSISTANT: Ok, please wait a  moment to check flight availability.

USER: Sure.

ASSISTANT: I have found a flight in Hawaiian airlines which is having connection 1 and the ticket fare is 300. Is it ok  for you?

USER: Please do not book flight.

ASSISTANT: Why, may I know the reason for not proceeding for booking?

USER: Fare is 300. Thanks.

ASSISTANT: Oh! Let me check once again for flight under your budget, ok.

USER: Sure.

ASSISTANT: Let me know your good name please to call you in better way.

USER: I am Laura Gonzalez.

ASSISTANT: Sorry, no airline is running a flight in your route under your budget limit because it is a longest route.