The front desk has an answering system, so id leave a message there including your docs name, your name and DOB. I've called on the weekend before and have been connected to an on-call operator. They cant answer any specific questions, but they may be able to arrange/cancel appts or at least leave a msg for someome who can.
Call and leave message. Or call first Thing tomorrow morning and cancel appt.
The answering service says you can leave a message to their voicemail.
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