the app constantly says connection errors saying the network is blocking it but it isn't
I'd bet its a kill switch issue, if not it could be related to an antivirus, proxy or firewall setting.
I don't use stock but I also use fedora, I had issues with the kill switch. There's two different kill switch options, my setup works much better with the simpler of the two. Also, I want to say fedora comes with the firewall enabled, plays into it being well ranked from a privacy standpoint I believe
Have you tried reinstalling yet? If you're in the UK that could explain the issue as ProtonVPN is apparently unlawfully being blocked out that way.