Working Families Flexibility Act of 2019 This bill revises requirements for the receipt of compensatory time off for private sector employees. Specifically, the bill authorizes private employers to provide compensatory time off to their employees at a rate of one and one-half hours for each hour of employment for which overtime compensation is required, prohibits an employee from accruing more that 160 hours of compensatory time, requires an employer to give their employees a 30-day notice before discontinuing compensatory time, prohibits an employer from interfering with an employee's right to or not request compensatory time off in lieu of payment of overtime compensation or from requiring an employee to use such compensatory time, and imposes penalties on employers who violate the compensatory time requirements set forth by this bill.