Hello.
user
Hello. How may I help you?
assistant
Due to sudden change in my trip dates I need to change my existing reservation. Can you help me changing my reservation?
user
Ok, I will help you with that before going to change your reservation I need your name to check it.
assistant
I am John Hall.
user
Sorry John Hall, there is no reservation found under your name to change it.
assistant
No problem, thank you for the information.
user
Thanks for contacting us.
assistant