Hello! I use the Google VPN that’s built into my Pixel when I’m not at home. Just a few hours ago it was working correctly, but now when I try to use it, it says “VPN by Google isn’t available for this account”. I’ve tried restarting, clearing the data and cache of the VPN, but nothing seems to be working. If anyone knows how to fix this, please let me know! Thank you 
I’ve also tried a second account and it just says “VPN isn’t available”
Happening for me too, on a Pixel 7
Happening for me on a Pixel 8 Pro too
Same. I’ve noticed it’s been on the fritz for about a week. Looking deeper into it, I’m seeing that same message you are.
No explanation anywhere, obviously, because why would anyone want that.
Same issue, is their VPN down maybe?
Happening for me too, on a Pixel Fold
This may have been resolved for me. I opened a support request about it with Google, answered a few questions and sent them some screenshots, got transferred around a few times without really anyone there knowing what to do about it, and finally gave up in exasperation.
But it was mysteriously working the next morning and has been 100% reliable for the past 2 days.