Help with this appointment bill?

The situation is, I needed a prescription for this chronic thing I get every year that I got again recently so I’ve been doing the rounds. I don’t remember well but I believe I was desperate last year and wanted an appointment at this clinic I haven’t been to much, I’m higher risk for covid and I didn’t wanna physically walk in anywhere so I used their phone call appointment option(they don’t even do webcam call appts), was like a 5 minute call, got my prescription, that was it. Fast forward to now, I’d completely forgotten about it, looked through on my old MyChart account I realize I got a bill for a $100 for that appt, my dad’s insurance covered $0, what’s up with that? Who do I call to sort this out because a five minute call for a copay of a hundred bucks is total bullshit. Do I call my dad’s insurance company, do I call the clinic and ask why my insurance didn’t do shit? Idk where to start on this and I don’t wanna just come out and complain at a random receptionist about something out of their control

Thanks.