Hello.
user
Hello. How may I assist you today?
assistant
Due to an emergency, I want to change my reservation. Can  you help me?
user
Sure, I will help you with that but I need your name to check the reservation details.
assistant
John Gonzalez here.
user
Sorry, I could not find any reservation with your name in our database.
assistant
No problem, Thanks for the information.
user
Thanks for choosing us.
assistant