Probably should call the dealer or whom ever you are current on payments with. If they have no issues and the guy didn't leave any information he stole your car report it..
If you are up to date and current on the payments then the other party has no right to take your vehicle. I have had several cars over the years that repo men think they can come to my business and take my customers cars. They can't and I have the police remove them. Call the bank like I said if you are current they need to return it.. But if you are NOT current on payments they can come and get it... If it is paid off.... Someone just stole your car..