Striking, thanks for the comment,

Please note that I typed 5.04 (with a dot), not a comma.

I was doing a manual account recharge (adding credits), where the user defines an arbitrary prepaid amount. On a localized system/keyboard setup, entering the dot did not alter the total due or warn me of a 100x increase before hitting the submit button.

Also, the core issue is the complete lack of a final checkout/confirmation step for an arbitrary recharge amount. In proper financial UX, clicking the primary button should trigger a modal stating: "You are about to recharge your account with $504.00 USD + $65.52 VAT. Total due: $569.52. Confirm payment?". Executing an instantaneous credit card charge on a single click while silently processing ambiguous inputs is precisely the dangerous design flaw I am pointing out.

Saludos,

It feels more like a writing exercise - too many extraneous details right from the start: "I am a LegalTech Attorney leading a developer team" feel necessary if you're telling a story, but is completely irrelevant if you're reporting an issue. And $5.04?? Who knows their spending requirements to that level of specificity?

Is it possible? I guess, but I doubt they're being honest about what was being displayed on the screen.