Hello.
user
Hello. How can I assist you?
assistant
Due to the inconvenience of  travel dates, I want to change my existing reservation. Can you please help me in changing my reservation?
user
Sure, I will help you with that.
assistant
Thank you.
user
May I know your name please?
assistant
Sure, myself Barbara Lopez.
user
Barbara Lopez, we couldn't find any reservation under your name in our database.
assistant
That's ok no problem, it might be changed by my manager, but he didn't inform me.
user
Thank you for reaching us.
assistant
Anyway, thank you for searching.
user