N.J. Stat. § 17:16C-29
Whenever a payment is made on such a continuing agreement after additional purchases have been added, the payment shall be considered as allocated among each of the separate purchases included, in full to the purchase made earliest in time, and the retail seller before repossessing or attempting to repossess any goods under any such agreement shall actually allocate in such manner all such payments made to him by the retail buyer. When the amount owing on any separate purchase has been fully paid, the goods so paid for shall become the absolute property of the retail buyer and shall not be subject to repossession for any subsequent default on the agreement. The retail buyer under any such agreement may at any time prepay the amount due on any of the separate purchases and in case of repossession may redeem any of such separate purchases by payment of the amount due on such purchase alone.
N.J.S. § 17:16C-29