My Company (us) Dropped Insurance On My Newborn

I work for a fairly large company (US based). I recently went on leave while we had our child. While On leave I had access to my employee workday for about 2-3 weeks before it was locked for security reasons (my leave was two months). However, after the birth of my child I was able to add them to my insurance through my benefits.

Everything was fine, I have her insurance card, got the tax form showing she was covered for the month of December. Had some hospital stuff billed to the insurance etc. Then we had to take her to the ER In February, when I gave them my insurance card it was declined.

I contacted insurance the next day and they looked into it and said that my daughter was covered from her birthdate to Jan24th. However, on Jan 25th when my company submitted my insurance, she was left off. Insurance told me to call my company's HR to have them resubmit my paperwork with her on it.

This is where my frustration really begins, after contacting my HR department (which is some admin team contracted by my company) they told me that I never submitted her into the system and that there was no data of her. While I was on leave, my company switched admin teams and during that switch over my child's information wasn't carried over.

I was then told I was supposed to submit my insurance to the old admin team, then turn around and submit it to the new one. I had no idea we even had a new admin team, I wasn't contacted by anyone requiring any more information or letting me know that I needed to do that. When I went into workday there was no where to do that except my usual benefits area, which was the old admin team.

I then put in an appeal and was told 10-15 business days before I would hear back. On the 16th business day I called them and my claim was denied (no one reached out to tell me this). I was told by my company' HR in the denial that I was given a handbook on how to upload things while on leave (I was never contacted by HR or given a handbook) and that I could look into marketplace insurance.

However, that wasn't even my issue outlined, I was able to upload what I needed to but how was I supposed to upload information to a completely different entity I had no idea about. When I spoke to a supervisor from the new admin team she said that in her opinion someone from my HR department should have reached out to me. I was told a second appeal was opened and I should upload documents supporting why my child needs affordable health care coverage...

I'm not sure what to do at this point, it feels like I'm getting a giant middle finger from my company and that no one is actually taking the time to see what the issue was. I'm so unbelievably angry and upset and I have to come into work as if my child is fine and I'm not swimming in debt just from the past couple of months. I completely feel like it's a clerical error or something by my company's HR. My newborn has had some medical issues and I'm already facings thousands of dollars of medical bills that I can't pay due to not having insurance.