I have been using Mullvad VPN, a paid VPN service from Sweden, since September or October 2021. Mullvad offers accounts for a flat monthly fee and never has sales or lock-in beyond a month. One interesting feature of Mullvad is that it does not request any information beyond what is necessary to make a payment, and it accepts payments in many formats, ranging from cards to crypto to cash sent in an envelope. Mullvad is now selling activation codes on Amazon. Among other things, I suppose that this is a good way to give the wonderful gift of a Mullvad VPN subscription to a friend or loved one (because what better gift is there?). As of July 26, 2022, the Amazon option is only available on the United States and Swedish Amazon sites, but Mullvad states that it is extending the option to Canada and several European countries in the future.
(Note: Also see my post on Mullvad’s free public DNS service, which does not require an account.)