Hello.
Hello, how may I help you today?
I made a reservation to go for a trip with my friends, but  due to my busy schedule I want to change my reservation. Can you please help me with the same?
Sure, we are here to help you.
Thank you.
May I know your name to check the reservation list?
Sure, my name is David Mitchell.
Please wait a moment, I will check your details and get back to you.
Sure, take your time.
David Mitchell, we are sorry to inform you that there is no reservation exist on your name to do modifications.
Not an issue, thank you for checking it.
Thank you for contacting us. Have a nice day.