The luhn test is failing for the MasterCard BIN 2-Series (222100-272099)
Sample Master Card:
2221 0012 3412 3456 12/18
- Note that those cards are not scheduled to be released until next month, so there's no way that that should be a valid card number (which is probably a good thing, since you should not be posting real card numbers here).
- But, also, the Luhn test is apparently not used for Diners Club enRoute cards, so there seems to be precedent for the idea of card numbers which don't validate with the Luhn algorithm.