I need help with Medal Of Honor (2010) game on EA App. (No Steam)

I purchased, downloaded, and installed Medal of Honor (2010). However, when I try to open the game, I get a pop-up that says "Enter your Registration Code Here." Please enter the entire Registration Code found in either your confirmation email, your game manual/product packaging, or your game card. There's already a code in the place it asks me to enter. When I click "Done," it reappears. I checked my email and didn't see a code there. When I searched, it said there should be a "Show Key" when I right-click the game, but I think that was something that happened during the Origin Launcher era. I couldn't find this "Registration Code." I purchased this game from EA App on September 19, 2025.