I recently added 80 bucks there. I emailed because it wasn't credited, and support said: "Exceed the minimum amount in a new topping up to trigger the topping up process; both previous and new toppings will be credited."
This is an old ripper's site still selling fake cards, logs, tools, etc.
It has good search engine traffic and 2-3 popular scam sites that post non-working carding methods and tutorials recommending buying cards from pluscards.cm
If you prepay or top up your balance, you'll lose money because you'll receive invalid generated data.
How can I verify the legitimacy of this scam shop?
Offer to make a purchase through any trusted escrow service, and you'll get the offer ignored, completely rejected, or provided with the contact of an escrow friend who will scam you using the intermediary service.
Please beware of such sites, of which there are many on the Internet.
