Red Alert 3 corrupt serial number

Hello, I 'eve been having issues with Command and Conquer: Red Alert 3, I've been trying several times to fix this issue however despite looking up all the solutions on the EA website & a few quick Google searches I still have not fixed my problem. So the exact problem is: Whenever I try to go online I get the error: "Corrupt CD key your CD key has been altered" or something along those lines. My brother and I both but the ultimate collection to game against each other but we're not having any luck in fixing the problem. I tried using the solution EA posted: https://help.ea.com/ca/article/invalid-serial-corrupt-registry-on-generals-zero-hour-and-red-alert-3 But that still doesn't help. I did everything the explanation asked but there was still no resolution. The only difference is with the invalid serial key that was posted is that there is a ] right beside Red Alert 3 in my reignited. Any help would be greatly appreciated!