Notwithstanding the provisions of this article, any failure to comply with any provision of this chapter may be corrected by the holder in accordance with the provisions of this section, provided that a willful violation may not be corrected, and a correction which will increase the amount owed by the buyer or the amount of any payment shall not be effective unless the buyer concurs in writing to the correction. If a violation is corrected by the holder in accordance with the provisions of this section, neither the seller nor the holder shall be subject to any penalty under this article. The correction shall be made by delivery to the buyer of a corrected copy of the

contract within 30 days of the execution of the original contract by the buyer. Any amount improperly collected from the buyer shall be credited against the indebtedness evidenced by the contract.