Cancelling a service, but they won’t get back to me

I have an appointment with a health provider. I’ve left 2 messages over the last week saying I can’t make my next appointment and still have not heard back. Every time I call, it goes to voicemail. I also left a note in their scheduling portal saying I’m cancelling the appointment.

Their policy is that you have to cancel at least 24 hours in advance. It is now the day of my appointment, and it is still showing as active.

The issue here is that I prepaid for 10 sessions, but decided I didn’t want to continue after the 2nd session. I’m hoping I can get reimbursed for the unused 8 sessions, but I feel like the provider is ghosting me. They also charge no-show fees so I’m worried I’ll get hit with that for my appointment that was supposed to be today.