In case of failure by any person to comply with the provisions of this chapter, such person or any person who acquires a contract or installment account with knowledge of such noncompliance is barred from recovery of any time price differential or service charge or of any delinquency, collection, extension, deferral or refinance charge imposed in connection with such contract or installment account and the buyer shall have the right to recover from such person an amount equal to any of such charges paid by the buyer.