This message appears when Google rejects the token. The usual causes are:

• Version mismatch - the keys were created as v3 but Google Recaptcha - Version is set to v2 (or vice versa). The version must match the key type from the reCAPTCHA admin console.
• Wrong domain - the reCAPTCHA site key was registered for a different domain than the one customers use.
• Low score - with v3, real visitors who score below the threshold (default 0.5) are rejected; lower the threshold via support or switch to v2 checkbox.
• Secret key typo - the Secret Key must be the one paired with the Site Key.

Correct the setting on the Google Recaptcha card; changes apply immediately.