I can't subscribe. Why isn't my money good enough?

I created my SWTOR account in 2011. I haven't been a subscriber for around 5+ years. I want to return.

I try to subscribe while obviously logged into SWTOR's site, also logged into the actual game as a free player, AND logged into my EA account on the same browser. 

I get a: "There was an issue accessing your account information.  Sign in and place your order again." error. It happens no matter my payment method (credit card or PayPal, I tried both). It also happens no matter if I try a monthly subscription or to buy a 60-day token.

When I click on the "Manage Billing" button, nothing loads. The loader just spins indefinitely.

My EA account is linked to my SWTOR account. When I click on the EA Account button on SWTOR's website, it says my account link is good. I use my EA account through my launcher to play games weekly without issue. I load the SWTOR game through its launcher, NOT through EA or Steam.

I've been trying to subscribe and researching wtf is going on for over 3 hours, and I'm losing all desire to play now.

Does anyone have any insights to help me out?