Ken Mumper purchased several prepaid Vanilla Mastercards for his family — only to find that each gift card envelope contained a blank Starbucks card.

And Walmart refuses to give the California man a refund.

When Mumper discovered the error, he took the cards back to the Chino, Calif., Walmart where he bought them. He even left one un-opened so the store manager could see for herself what he was talking about.

“And she opened it and sure enough another Starbucks card,” the father told KNBC-TV.

The Walmart manager told him the store was aware of the problem and that they had already pulled the faulty gift cards from their shelves – but she added the mistake was not their fault and she refused to give the father a refund.

“The fact they were aware that there was a problem but they were not willing to take responsibility for it was quite frustrating,” Mumper said.

The Walmart manager suggested the California man contact the Vanilla Mastercard distributor. Not looking for trouble, Mumper took her advice and contacted the distributor. After several hours on the phone, he was eventually told by the distributor to go back to Walmart.

“These large corporations sometimes they don’t care,” he said. “Their interest is only in the almighty buck.”

KNBC-TV decided to look into Mumper’s claim and found that the same Walmart was still selling faulty gift cards one day after Christmas.

“(T)he packaging looked normal — no tears or use,” the news team reported, noting that the cards appeared to be in pristine, untouched condition.

So the news team decided to buy four prepaid Vanilla Mastercards. What they found were two blank $25 Walmart gift cards, a blank American Express card and one used prepaid Vanilla MasterCard worth only 2 cents.

The news team went back to the Walmart to resolve the issue. Like Mumper, they were refused a refund and told to contact the Vanilla Mastercard distributor with their complaints.

“We have always bought at Walmart but if they won’t stand by their products and carry on like this during the holidays with a return … as far as I’m concerned I am finished with the store,” Mumper said.

A Vanilla MasterCard spokesman said “he thought this was package tampering not during distribution — but sometime after delivery,” KNBC-TV reported. “He vowed to refund people who may have fallen victim.”

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