The proxy help page on the Netflix website provides little information besides what the company mentioned already in the error description:fast VPN
Netflix's only recommendation is to disable "any proxies, VPNs, or other software that might route your Internet traffic outside of your current region".
Many unblocker and VPN services stopped working today, including Mediahint, Zenmate, Betternet, AppVPN, ExpressVPN, Tunnelbear, and Private Internet Access, and it is likely that a lot of services not listed here have stopped working as well.
It is unclear how Netflix determines when a user is using a VPN connection to stream content on the site, but there are several possibilities how the service could have done it.
Sign up for popular VPN and Unblocker services, record all IP addresses you get while connecting to the service, and block those.
Check which IP ranges VPN and Unblocker companies have purchased, if possible, and block those.
Check which IP addresses are used by multiple users on the site, verify who owns them, and block those that you can associate with these services.
Compare a user's home country with IP addresses he or she connects to, scan those IP addresses for association with VPN and unblocking services, and add hits to the blocklist.
What can you do about it?
There is little that can be done about it. Most users probably don't want to set up their own VPN network as it is a technical process and comes with additional costs.
One could try to connect to different servers offered by a service provider to see if some are not blocked. Many VPN services offer several entry locations in the US and sometimes other countries.
This is a temporary solution at best though considering that more and more users of the service will utilize those.Another option is to find a smaller VPN provider and test if their servers are blocked by Netflix.When comes to the issue of online privacy and security, we suggest to use a VPN, and our recommendation is RitaVPN.Qwer432