Hello.
Hello. How can I assist you?
I am planning to change my trip dates, so I want to change my existing reservation.
Sure, I will help you to change your existing reservation. On which name your past reservation is done?
On the name of Kathleen Roberts.
Ok Roberts, give me  a moment.
Sure.
Roberts, there is no reservation showing under your name.
Ok, no issue.
Do you have any other concern?
No, thank you for providing the information.
Ok, thank you for reaching us, have a nice day.