Hello,. I am Nicholas Smith.
user
Hello, how may I serve you today?
assistant
I would like to change my existing reservation. Due to my family meeting has been preponed.
user
Sure, please wait for a moment I will get back to you.
assistant
Ok.
user
thanks for waiting, we have not found any flight reservation with your given name.
assistant
Thank you for your service.
user
Thanks for choosing us.
assistant