Hi. I am Karen Lee.
user
Please let me know, what kind of service your looking for?
assistant
I am planning to change my reservation, can you help me in changing  my reservation?
user
Sure, we are happy to help you. Please wait for a while.
assistant
Ok.
user
Sorry to say that, there is no active reservation found on your name.
assistant
That's ok, thank you.
user
Thank you for opting us.
assistant