Hello, I William Thompson.
user
Hello, how may I best serve you today?
assistant
As my plan to visit  Washington was preponderated due to personal issues. Would it be possible to modify my existing reservation?
user
Sure, please wait for a while.
assistant
Ok.
user
Thank you for waiting. There is no reservation found on your name.
assistant
No problem, thank you for the information.
user
Thank you for making us to serve you.
assistant