Trying to add software token, registration code doesn't work

I've tried on a couple of occasions now to add a software token (via the Android app) to my account, but the registration code I'm getting on the email just won't work. I've checked that the DOB matches what's registered under my account info page and is entered in the right format, tried my username in all caps, all lower case, and every variation thereof, and I've re-keyed the registration code multiple times, but the app just doesn't want to accept it. Any bright ideas about anything that might be going wrong, or do I just keep retrying every 24 hours until the system gives me a registration code it feels like accepting?