Hello.
user
Hello, how can I assist you?
assistant
I want to change my existing reservation, can you please help me with this?
user
Yes, I am here to help you. May I know your name please?
assistant
I am Joshua Collins.
user
Ok, please wait a minute I will get back to you.
assistant
Sure.
user
Thank you for your time, sorry no reservation found  on your name.
assistant
Ok, no problem.
user
    Thank you for reaching us, have a good day.
assistant
Thank you for your information.
user