If you have anything related to CSS (Counter Strike first person shooter game) on the card, then the credit card processor will argue that you bought skins for the game.
In Counter Strike there are weapons, there are different appearances, the value of the skins is usually between €0.01 and €1 million. The latter is very, very rare, but it is not uncommon for a skin to be worth €500. I play the game myself and have an inventory of around €6000.
In the game you can buy so-called loot boxes via Steam (game operator). Loot boxes are classified as gambling in some countries because the drop of a valuable skin is very rare and you can lose a fortune there.
Then there are other sites where you can link your Steam inventory and sell the skins for real money. The game operator does not prohibit it, it is a common business model.
If the person who debits the card says that you have bought such weapon skins, then make a data protection request to Steam to see if a Steam account is registered in your name, because you can only use the skins if you play the game, otherwise it is worthless. It is also important to know that such skin purchases can only be made in connection with a Steam account. Simply registering with an email and password does not work.
When you buy this virtual item, a so-called bot transfers the purchased item to your inventory and you have to confirm the transfer several times.
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