usadiscountwarehouse.com Selling cheap knoco off junk SD cards that don't work Cape Coral, Florida

I ordered a 512 GB micro-SD card which came with free 64 GB card. After receiving them, I found out they were cheap junk. Kept getting error messages and lost files transfered. I contacted the company (via e-mail) They answered quickly, apologiziong and suggesting it was a formatting problem, and telling me to download this free software and it would fix it. I did as instructed, and after the software "formatted" the card, Windows wouldn't read it, and said it need formatting. Reformatted with windows, and the same process ensued. Advised the compay, they quickly offered refund/ exchange. I chose refund, and sent the cards back according to their instructions. USPS verified they received 8/1/16. Then, silence. I checked my account, no refund. I contacted them 8/7/16, then again this morning. Nothing. No acknowledgement, no response. I even advised that if I didn't get a response, I would file this complaint, but nothing. I also filed a complaint with the BBB.