There's a change/edit button (I can't get the profile page to load so not sure which it is.) you need to click on before you can make changes.
Once I found that button then I was able to click the Opt-In.
I'm happy about this news, because I either lost or threw away my previous card, was looking for it earlier this year and couldn't find it anywhere.
P.S. Disappointingly, every time I login, it seems it won't accept my password and I have to change it. I just changed it a few months ago. Are our passwords being reset every couple months or something? Not a real big deal but sort of an unnecessary pain. Maybe it's just me? I don't care too much, it's an easy fix, but I'm not accustomed to having to reset my password like EVERY time I go to login again on most websites. My 2 cents.
Cheers all.