customer: Hello, I am Donald Moore. 
 agent: Hello, How can I aid you? 
 customer: I need to change my existing reservation as my dates of trip are postponed. 
 agent: Ok. 
 __ 
 agent: Sure. Please wait a minute. 
 customer: Sure. 
 agent: Thanks for waiting, There is no reservation found with your name. 
 customer: Ok, thank you for kind service. 
 agent: Thank you.
customer: Will you help me in changing my reservation.