Robot Tycoon invalid code issue (Image via Roblox || Sportskeeda) It's possible that certain codes may not work alongside others, and some may expire sooner than others. If a code doesn't work for ...

Search up "EZ Robot Simulator" in the search box, launch it, and wait for it to load. Locate and click on the "codes" button screen, after which a new window should pop up on the screen.