Test after enabling. Check login, registration and Forgot password in a private window. If any fails with reCAPTCHA token is required, a browser extension may be blocking Google's script; try another browser, then contact support if it persists.
Strict scores block real people. VPNs, office networks and brand-new devices score lower. Don't go above 0.7.
Script blockers. Shoppers who block Google scripts can't pass the check.
Google outages. If Google can't be reached, requests are allowed through.
Not on checkout. Guest checkout and order placement aren't protected by reCAPTCHA; use OTP Verification and Payment Restrictions against fake orders.