Hi.
user
Hello. How may I help you?
assistant
I am Alexander Martin. Owing an emergency want to change my reservation, can you help me with it please?
user
Sure, I am happy to help you. Please wait, let me check your reservation status in our database.
assistant
  Ok.
user
Sorry, there is no reservation found under your name in our database.
assistant
   That's ok, thank you for the response.
user
You are most welcome and thank you for choosing us.
assistant