If the pluto.tv/activate page isn't working or your code is rejected, try these quick fixes from Pluto TV Support : How can I sign in to my Pluto TV account?
: Ensure your Pluto TV app is updated to the latest version (at least version 8.5) through your device's app store (e.g., Roku, Amazon Fire TV).
Old browser data can interfere with the activation handshake. Fix: Try using an “Incognito” or “Private” window in your browser, or clear your cache and cookies.
alongside the text code; scanning it with your phone's camera will take you directly to the activation page with the code pre-filled. Expiration : Codes typically expire within 5 to 10 minutes