I keep getting billed by doctors office for copays I’ve already paid

I do not understand why my doctor’s office (NYU Langone) keeps mailing bills to my home for copays that I have already paid when I have my appointment, which I do every time. My health insurance is Fidellis. I had hoped to get some explanation for why this kept happening. Even though I paid that amount in full when I went to my doctor’s appointment, the most recent notice claims that I still owe $75, which was collected by the debt collector.

Hey comrades,
File all medical bills, payments, and correspondence.
and Continue pursuing the issue until it’s resolved.also
Understand patient rights and consumer protection laws.

I’ve had something similar happen with my bills too. Sometimes, even if you pay at the time of your appointment, the billing system might not update correctly or there could be a mix-up with your insurance. It’s worth calling NYU Langone’s billing department directly to clear things up. They can usually fix these mistakes and make sure you’re not charged twice. I found that talking to them usually sorted out the issue for me.