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