Hi.
Hello. How can I assist you at this moment?
Owing to an emergency, my planned trip to Yosemite adventure got postponed, so I want you to change my existing reservation.
Sure, I am happy to help you with that. Can I have your good name please to check your reservation status?
Sure, Linda Rodriguez here.
Ok, please wait a moment.
Sure.
Sorry Linda Rodriguez, no reservation has found under your name to  change.
Ok, no worries at all. Thank you for your information.
Thank you for choosing us, have a good day.