Months after the hacked education software maker PowerSchool paid a hacker’s ransom to delete the company’s banks of stolen student data, at least one school district says it is now being extorted by someone who said the data was not destroyed.

Cybercriminals demanded ransom payments from school districts nationwide this week, using millions of K-12 students’ sensitive data as leverage after the files were stolen from education technology giant PowerSchool in a massive cyberattack late last year.

In December, a hacker gained access to personal data for students and teachers across the world in the database for the PowerSchool student information system. PowerSchool had told users that the hacker had destroyed the data but now that person is trying to get money from individual school districts.