The system is NOT useable for people like me who travel internationally and do not use their home cellphone while away, so cannot receive the SMS codes. An email confirmation is the essential alternative and is one which satisfies the security standards required of major banks.
With respect, this totally limited system has not been thought through and is clearly aimed only at folks who do not leave their home country for the big wide world beyond its shores or who use different cellphones when overseas. I will be happy to activate it when this anomaly is corrected.