This service is BS. I just went there and it gave me a random torrent, "Jennifer Lopez Papi" (or something like that). I wouldn't get anything of JLo's, even if they gave it to me free.
Either you are behind a masquerading NAT, or perhaps your ISP rotates IP addresses and somebody else was using your address the other day, or just maybe your WiFi router isn't as secure as you hoped, or...
The service neatly highlights the caveats of matching people to IP addresses.
https://torrentfreak.com/the-pirate-bay-tricks-anti-pirates-...
It also didn't mention things I have pirated off of public trackers, so, meh.