Yeah, many people. Been a common complaint for awhile now. Difference with what you report though is that yours happened much much more quickly than, to my knowledge anyways, has been other guy's experience. Card On File at 5D used fraudulently after much much more time being On File there, than you experienced.
It did happen to me as well, about 6 weeks ago. Two small (testing the waters) fraudulent charges Bank caught it though nixxed card issued me a new card.
I feel like I haven't come across a "response" from 5D in the quite a few lengthy thread discussions that exist at this forum and others ON THIS MATTER but the sense, like: Overall "Feeling" of people is its "Asian Processors", Credit Card Processors "3rd Party".....and not "in house" with 5D themselves but to me a lack of response from 5D to this very very Grave Issue is Troubling.
Maybe 5D has issued a response on this and I've just not seen that response.
Theres really no Rhyme nor REASON IMO with some of these books: 5D seeming to have little or NO concern about what you describe: CCs used with them being then used to steal (and a few guys got very very hurt....1000s of $$$$, most otherwise and like me just had to get New Card) 5Dimes seemingly giving absolutely Zero Fucks about this. And BetDSI totally transforming their whole platform, offerings much more Limited now, Withdrawal Limits spoken of, after this very recent dramatic change said to be a Clean Break from The Bookmaker/Bet Cris Family and a "reveal" that DSI now somehow "affiliated" with BetLucky.ag or some other D Graded Book with "Lucky" in their name...
Odd stuff afoot and genuinely, reading some of whats been reported by bettors its hard to emerge with an impression that "certain books" give a damn. Which is puzzling cuz it seems like they should if for no other reason that the Massive Spikes in Bad Experiences being reported, such as what you describe, would surely affect their Bottom Line (income, $$$$) in a negative way.