Hospital Keeps Sending Me A Mis-coded Medical Bill, And It’s Now Impacted My Credit.

I apologize if this is too specific a question: I'll delete if so.

My husband and I are undergoing fertility treatments, and we were sent to a local hospital to get an HSG test since my OBGYN doesn't have the equipment. An HSG is an X-Ray that looks at your uterus and fallopian tubes, just in case folks aren’t familiar with the procedure. It's a simple, quick procedure, and I was told it would cost around $400 out of pocket if insurance didn't cover it.

Anyway, months ago I got a bill for over $2,000 for “Cardiovascular services”.

I have never had cardiovascular work done. I've done a bunch of googling, and there's no way the procedure would be coded as, “cardiovascular services.” I called them right away assuming it was a mistake, and I was told that they’d look into it, and that no news was good news. I was told to wait for a new bill before I pay. I never received any follow-up. Flash forward to today, and I get the same bill for cardiovascular services, but this time it's impacted my almost perfect credit score that's taken ages to build because I haven't paid it.

What do I do in this situation, and if they miscoded and didn't rectify, is it legal for them to keep billing me for it/send me to collections for services I never received? Do I just keep calling billing to rectify this, or do I pay the bill and worry about it later? I was not prepared for this kind of bill and a hit to my credit score on top of other expensive fertility treatments.

Thank you for any insight!