Hello.
Hello. How may I help you for today?
I am Sarah White. I am planning to change an existing reservation because of some  urgent work at office.Can you please help me out to change reservation?
Yes, I will try for best assistance. Hold on for a second, I will check for your previous reservation.
That's really great, take your own time.
Sorry to inform you that there is no reservation found on on your name in our database. Anything else I can help you with?
No, I don't have any other plans.
Thank you for reaching us.
Thank you for your service.
Feel free to reach us anytime.