Stole my vehicle

I got into a car accident in 2019 with my Nissan Xtrail and sent my car in for repairs, my car was being fixed by Andrew Mkhonza whom we paid over a period of time by installments. We struggled to get certain parts for the car ourselves hence the car has been with him since 2019. We communicate with him monthly regarding the progress of the car, this past Sunday we phoned him to advise that we will be bringing the last part for the car and he did not answer his phone. We proceeded to his home anyway, on our way to his home we were met with our car being driven by someone else who confirmed that they bought it from Andrew Mkhonza. Andrew then answered his phone and continued to lie and say the car is safely stored at Winterved Enterprise Hub where he worked. He has not offered an explanation to date all he said was that he is not getting involved we need to contact the guy who bought our car without our permission.