Dealing with these cards will bring a lot of risk to you, from being scammed into buying used cards/codes and ending up buying a stolen one.
The problem with this type of card is that you can not know that you were deceived only after trying to use these cards, so they are sold from trusted parties or using escrow services such as localbitcoin.
Even with the use of an escrow service, you may expose to risks such as buying stolen cards that may lead you to jail.
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