Does buying a car in installments from Nasser Bank, which sells the car to the buyer in installments without giving him money, count as usury, and how can one atone for that if it is unlawful, given the inability to reverse the sale?

Purchasing a car in installments is permissible if the bank first buys the car and takes ownership of it, then sells it to the customer in installments. However, if the bank pays the price of the car on behalf of the buyer and then reclaims the amount with an increase, this is not permissible. The expiation for engaging in a usurious contract is through repentance, seeking forgiveness, regret, resolving not to return to it, and immediately abandoning it or rectifying what can be rectified. If the transaction has already concluded, then one must repent, feel regret, and resolve not to return to such usurious dealings.