I used to buy MO at my WalMart using my OV (from CVS) till now. Today, for my surprise, When the cashier asked me to swipe my card, the register spit out a receipt saying the above mentioned message.
She tried again, no go. As soon as I swipe, the swipe pad shows a sign screen (like we get after we swipe for a purchase using CC)
My assumption is that now WM is treating OV as CC instead of debit? Any one else been successful getting OV-> MO today?