Hospital waited to bill me, now wants me to pay big?

At the end of July, 2021 my husband and I welcomed our son into the world. He came under slightly dramatic circumstances as I developed HELLP syndrome and had to ride an ambulance to a second hospital. Then he had low blood sugar. He was transfered to the NICU for a few days before we were both discharged. We both recovered completely. Went on with our happy lives.

Fast forward 1 ½ (almost) years to December 2022. I get a bill from the hospital for my son’s birth. Now my insurance provider has stopped offering health insurance so my company switched providers in August 2022. The bill is $9,000 and they are saying they don’t have insurance on file. I call them and tell them my old insurance info. They thank me and about a week later I get a letter saying they couldn’t add my insurance since they don’t have the card. I call them and tell them the info again. About a week later they say they cannot add my insurance as it isn’t “timely”.

At this point, I’m fuming. I contact the insurance company, though they are no longer doing health insurance. They tell me that the hospital has to send them the claim. That it’s very odd that they would claim to not have the insurance as my son had to be pre-approved for his NICU stay.

I call back the hospital and share this with them. They say that the insurance provider has to request the bill. They also say that according to their records, they called the insurance provider and they said my son wasn’t on my insurance. I called back the insurance and they said that they have no record of the call and that they had to pre-approve the NICU stay and they paid thousands in other bills for this child (from the original hospital) so why would this have been any different.

I’ve called each of these locations weekly since December. Nothing has been solved. The insurance is saying that once they get the claim, they can deny it and write on the denial that this was due to the hospital, not the me, not being timely and then I can sort this out but this has been keeping me up at night with worry.

The hospital has had my phone number incorrect in their system (I’ve changed this three times with them). They have had my incorrect email (I’ve changed this twice with them). Also when they did finally send the claim, it was for a much larger amount than what they had charged me with ($2000 more) and the insurance company didn’t know why.

I spoke to someone with the hospital billing this week and she tried to say that I am at fault because I didn’t get the insurance info to the hospital within 30 days of my son’s birth. I am scared that after all of this fighting that will be my downfall. They had my insurance info and I added my son to my policy within 30 days of his birth. I have proof that the insurance company says he was added in time.

Also, in case it’s worth noting- the hospital had my phone number one digit off, so that happens to be my siblings number. So they did not try to call or contact me via phone at all until a month after I got this bill.

I believe the law is 180 days until a medical bill goes to collections but we are 60 days into this fight and I am scared. What steps do I need to be taking here? I am in Wisconsin if that matters.

Thank you in advance.