Nintendo 3DS no longer works after r4 card?

A friend gave me a card for my birthday that had 500 games on it. Apparently he ordered it from somewhere on the Internet.
I played with it once and everything was fine. But when I used the card a second time and connected my Nintendo to another DS, the error message came up at some point: "An error has occurred. Turn off the DS…" and then try again or something like that.

If I switch on my Nintendo now (even if neither this card nor another game is in it), the same error message comes up every time after about 5-10 seconds without being able to start a game. I can't even go to Settings and do a factory reset on my Nintendo before the message comes back.
I've tried turning the wireless switch on and off and taking out the SD card. Everything didn't work out. Is it possible that Nintendo deactivated my 3DS, so to speak?

Yes. I also don't understand why you don't just pay money for the games instead of using such a card.
sorry but somehow it's your own fault

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