They appear to be stating that they purchased a car from the lessor at the end of the lease term, with the lessor paying the 'end of lease' purchase price to the lessee. Apparently the car being leased in a state that only charges sales tax on the cost of the lease as opposed to the full purchase price - meaning that the lessor was supposed to pay sales tax on the buyout amount. Apparently the lessor did not pay the sales tax, leaving the OP owning sales tax on the purchase from the lessor and also unable to register the car without paying the sales tax that the lessor failed to pay when buying the car from the lessee - effectively having to pay double tax to register the car.

