NGLSync Troubleshooting and Support Sometimes problems can occur when managing your MindTap courses through NGLSync. Google Classroom Students Can't Access NGLSyncYour course page shows the error message Students cannot be registered in your course until you correct your permission settings or unlink Google Classroom. Google Classroom Roster Not SyncedIf changes you make to your Google Classroom roster do not appear in your NGLSync roster after a few minutes, refresh your Google Classroom roster. Students Asked for PaymentYour K-12 school district has purchased access to MindTap for its students, but when students create accounts and sign in at the main Cengage home page, they are told their trial access will expire and asked for payment. School Not ShownWhen you click Begin Registration, your school is not listed.