You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How may I assist you today?

USER: Please change my existing reservation.

ASSISTANT: Ok, I am here to help you. Can you provide your name?

USER: I am Brenda Campbell.

ASSISTANT: Brenda we have found reservation on your name.

USER: Ok.

ASSISTANT: Please share your willing travelling dates.

USER: Please book a ticket from Denver, CO-DEN to Phoenix, AZ-PHX. Travelling dates are from 07/14 to 07/16.

ASSISTANT: Ok, give me a while I'll be back with your flight details.

USER: Sure.

ASSISTANT: You have a Frontier airlines with no connections. Do you like to proceed?

USER: Please do not book a ticket. Thanks.

ASSISTANT: Ok, would you like to have any changes?

USER: Price limit is 1000. Connections limit is 1.

ASSISTANT: Ok. We don't have flights with 1 connecting limit.

USER: Please book a ticket. Thanks for the help.

ASSISTANT: Thank you.