Hello. My name is Dennis Martin.
user
Hello, how can I help you today?
assistant
Due to sudden change in our plan, I would like to change my existing reservation. Can you help me?
user
Sure, I will help you in changing your reservation. Let me check your details in our database.
assistant
Sure, take your time.
user
Sorry Dennis, I have not found any reservation by your name in our database.
assistant
That's fine, thank you for the information.
user
Thank you for contacting us and have a nice day.
assistant
Welcome.
user