Unable to remove EA Account from Xbox account

I have an Xbox account: Mwahagga

I've been trying to link it to my EA Account, however every method I've tried, results in an error. For example, via the Win10 Xbox app:

I've both chatted with and made multiple calls to EA Help. During my phone calls, the cause of the problem has been found. Apparently, there is an EA account already linked to my Xbox account. Neither person I spoke to on the phone was able to tell me anything about this mystery EA account other than:

• It is a child account
• It has no email associated with it (how?)
• It has no parent account email associated with (definitely seems broken...)

Things they could not tell me:

• A username
• When it was created
• If there was a game tied to it
• How to unlink it

I have tried signing in to the EA help website using my Xbox account:

After signing in, it prompts me to link an EA account acting like I have no EA account already connected even though supposedly I do:

If I try to link my actual EA account, I get stuck at this step:

Click "Next" doesn't do anything. The following webcall gets made and redirected but nothing actually happens. I can keep click "Next" more but the same webcall gets made with no result:

To sum up:

There is an apparently broken EA account linked to my Xbox account

There is no way I can unlink this account

So far, EA Help has refused to unlink it for me