Japan’s financial watchdog on Thursday ordered Sompo Japan Insurance Inc. and its parent Sompo Holdings Inc. to improve their operations over their involvement in used car dealer Bigmotor Co.’s insurance fraud scandal. The major insurance group maintained business with Bigmotor despite being aware that the dealership had been making fraudulent insurance claims, the Financial Services Agency said. The watchdog demanded the insurance firms rectify “the corporate culture in which the companies prioritize their profit over that of their customers,” and clarify management’s responsibility and stren…