Alright this is the long story.
I have a PS3... When GTA 5 first came out, I wanted to purchase a shark card. I don't have a lot of time to play games... so making money in the game to buy things would be pretty much next to impossible. I'm self-employed and work a lot...
So I tried to register my debit card with Sony.. and it kept saying there was an error with the card. My bank said everything on their end was fine... I came up with the idea of just getting the PS store gift cards... so I did that and purchased a shark card.
Well... I'm out of in-game cash, and wanted to do that again. I went to try registering my debit card again, this being many months later from the first time I tried, and the box where you enter all that info (on my desktop pc) just closed... so I figured it didn't work.
I then went to the store and bought 3 cards... came home... put the shark card in my shopping cart, and pressed checkout or whatever... and low and behold, it worked.
I'm in NJ, USA... Not sure if they can be used outside of the US.