Log in on simplephysx.com,(http://simplephysx.com) choose a subscription, then open Product & Keys in your profile and copy your Product Key. Treat it like a secret (don’t commit it to git or share it publicly).
“Product & Keys” is visible only when you are logged in and have an active subscription. If you just subscribed, wait a moment and refresh, then try again.
Re-copy the Product Key from Product & Keys and re-run the Setup Wizard. Auth errors usually happen when the key is pasted incorrectly or an old key is used.
