Those that are having problem getting MasterCards approved, there is a nationwide problem. Vital is blaming MasterCard and MasterCard is blaming Vital. Merchants are seeing CV:Failure:CV error codes when trying to approve them.
Anyway, Vital has a temporary fix, but it may take 24 hours for it to take effect. Contact them at (866) 634-2099 - must have V# for help
Or maybe just wait till tomorrow for it to fix itself.