Lauryn Hill allegedly owes a substantial six-figure sum in back taxes, more than a decade after she spent time behind bars over issues with the IRS ... but the legendary singer’s spokesperson tells us the entertainer is handling the matter. According to official records, the New Jersey Division of Taxation filed two separate liens against the Grammy-award-winning entertainer. The first was over an unpaid debt totaling $133,246 ... and the second was over $758,912.02. Both liens remain active in