Hello. Thomas Carter here.
Hi. How can I help you? Mr Thomas Carter.
Actually, I made my booking with wrong dates, so I want to change my existing reservation. Will you please help me?
Sure, Mr Thomas Carter give me some time to check your status.
Sure.
Mr Thomas Carter  I am sorry I could not find any reservation on your name.
It's alright.
Thank you.
Thank you for your service.
Your welcome.