I found a MyMathLab code in a sealed booklet from a few years ago, maybe it'll help someone. lmk if it works for you (or if it doesn't)

That’s nice of you! Hope it works for someone.

It says, "That ID didn’t work." when I tried to register.

Please be sure to comment either if you use it, or if if you try to use it but it is expired, so that other people will know not to spend time trying to get it work.