Hello,.
user
Hello, How may I help you today?
assistant
Please help me in changing my existing reservation.
user
Sure, Please provide me your reservation details.
assistant
OK, My name is Betty Allen.
user
To proceed further, Please provide your source and destination details?
assistant
The source airport : MA-BOS, Destination airport : GA-ATL.
user
Thank you for providing your details, Please be online I will check and revert back to you.
assistant
Journey dates  from : July/01 and to July/03.
user
Thank you for being online. As per your requested details, we cannot provide you the flight on specified dates.
assistant
OK, Thanks for the information.
user