Having a car registered in your name does not imply ownership. My son's car is registered in my name, however it is his car. A receipt for purchase made out to you is proof of ownership.
I crossed this bridge sometime ago when I had a relationship end, whereby I had my ex's mothers car that we had purchased a month before off her, and I registered in my name. She rang and demanded her car back just to be spiteful. At that point I thought she could stick it as the car was registered to me, but then discovered that it meant nothing and that I needed to provide a receipt as proof of purchase, which I didn't have. (Another lesson, get receipts even if it is family.)
For those interested in the outcome, my daughter was involved in a car accident in the car later that week and it was written off. Suddenly the cow didn't want her car back!
A bit off topic I know, but in WA it is the opposite. Whomever's name the car is registered in is the legal owner reglardless of who bought it or who financed it. Speaking from personal experience, many years ago during a marriage, I bought a car and financed it, but registered it in my ex's name, when the marriage ended I wanted the car back but the police told me that since it was registered in her name it was legally hers. The only option I had at the time was to do a voluntary reposession by the finacier and then reclaim the car. Turned out even that wasn't correct as the ex just told the tow company that they couldn't take it. Two months later when it ran out of rego, she handed the plates in and told the financier to come and get the car. I told them to sell it and pay the loan out, but they told me I had better go look at it as they did a valuation and it was worth $1500, and the loan was still about 6k at that stage. She or her cronies had trashed the car and taken everything out that wasn't screwed down, someone even removed the A/C controls, rammed a screw driver through the circuit board and refitted it. I paid the amount in arrears, took the car home, fixed it, reregistered it and kept it for another few years after that.
Two pieces of advice arise from this tale of woe, do not ever do a voluntary reposession, as it will stay on your credit file for 7 years, sometimes longer and will affect any future credit applications, and the second is always register a car in your name if it is financed by you.
To the OP, contact the previous owner and ask them to notify the relevant authority that the vehicle has been disposed of and then pay the transfer into your name ASAP.
