Hello.
user
Hello, how may I assist you?
assistant
I am Benjamin Adams. I want to change an existing reservation, due to my exams has been  postponed. Can you please change my reservation?
user
Sure, I am here to help you. Please wait a moment I will check your details and proceed further.
assistant
Sure, take your own time.
user
Sorry to say, I did not find any details in my database regarding your reservation.
assistant
That's fine. Thank you for your help.
user
Thank you for choosing us, have a nice day.
assistant