customer: Hi. 
 agent: Hello, How can I render you today? 
 customer: I am Christopher Hernandez. 
 agent: Ok. 
 customer: I want to change an existing reservation due to sudden change in my trip. 
 agent: Ok. 
 customer: Can you help me? 
 __ 
 customer: Ok. 
 agent: Please wait for a while. I will revert to you. 
 customer: Ok. 
 agent: Thanks for your time, but no reservation was done previously to proceed further. 
 customer: No issue. Thank you. 
 agent: Thank you for choosing us, Have a nice day.
agent: Sure, I will help you out.