PS4 thinks I'm a sub account even though I already upgraded?

So basically I want to renew my PS Plus subscription, so I upgraded my account from a sub account to a master account through my web browser. Then, I log onto my PS4, try to buy it, and it says I'm still a sub account. So I look through my settings, find where you upgrade on the PS4 itself, but I keep getting an error, presumably because my account is actually a master account. Any idea on what I should do? This is starting to get really agitating.