Unfortunately, Netflix doesn't work through PIA, they apparently aggressively block IP ranges from most major VPN providers, so the issue isn't specific to PIA. This is a bit of a "screw you" to privacy-conscious people, but then again Netflix have their own issues to deal with (whether legitimate or not is a different conversation). Two things I do on occasion: have a box dedicated to watching Netflix, that isn't on a VPN (which might not help if you're trying to bypass national licensing restrictions), the other is to tunnel my connection to one of my servers through the VPN, which works fine, though it's a bit of a pain.