Hi.
Hello, how can I assist you?
Owing to an emergency, my planned trip to Washington got postponed. So I want to change my existing reservation.
Ok, may I know your name please?
Sure, I have a recent reservation with name Benjamin Nelson.
Ok, please wait for a moment.
  Sure.
Sorry, there was no reservation found with your name.
Ok, no worries at all. Thank you for your help.
Thank you for opting us.