Hello.
Hello. May I know your sweet name please?
My name Jacob Green.
Nice to meet you Jacob. How may I assist You today?
I want to change my reservation can you help me?
Sure Jacob, please wait for a moment, I will get back with details.
OK.
I am really sorry for to tell you, I cannot find any reservation with your name.
OK. Thank you for checking.
 It was my pleasure, thank you for contacting us.