Keyless entry pad programming 2002 Sunfire

I am so brilliant! I managed to lose a keypad for my 2002 Pontiac Sunfire. I purchased another with the same code on the pad back GM1626207499. All other information on the pad is the same as the one I still have that works. The replacement appears new and inside and outside to be OEM. Batteries on both units new. The original car pad works fine. I have tried the by the side of the care method and the turn the key while pressing button method and the standing on hands while entering a code and naming the states in alphabetical order methods without luck. How can I match these two seemingly identical pads to my Sunfire so I can once again have a spare?

Are you talking about the remote keyless entry?

Yes. I lost one of the black keychain remotes and have another that I wish to match to my car. It is new but numbers match my one original pad I have.