What do I do, previous owners debt on car.

So today I sold my car and on the PPSR report it shows as debt outstanding on the car, I didn’t know this when I sold it and neither did I know when I bought it from the previous owner. When I checked the PPSR report when I bought it I only looked out for written off or stolen records, and I never saw anything about debt. The previous owner before me was the first owner, and they’re not contactable. Their number is non existent and their carsales profile is deactivated. I’m taking the car back, now and will have to deal with it. What do I do though? Is there a chance it’s a system error? I’m actually so pissed off right now. There goes my new car.