I propose that employers should be prevented from opting out of social security contributions (pension and disability insurance, compulsory health insurance, parental care, unemployment) until all retroactive contributions have been paid.
In practice, this would mean a safeguard that an employer could not dismiss an employee (on expiry of the contract, termination of the employment relationship for any reason) until all his contributions to the State have been paid. This would avoid millions of euros in debts, the frustration of workers who only find out when they lose their jobs that their pension and invalidity insurance contributions have not been paid for years, and the constant firing of old and hiring of new victims of unpaid contributions.