To re-enroll the students back to their previous grades please follow below steps:
Admissions > Enrollments
Select Enrollment Status as "Un-Enrolled" and Search
Click on the three dotted icon and select "Re-Enroll Application" option:
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System will ask for confirmation “On application re-enrollment, system will generate new invoice(s) if enrollment grade have associated fee type(s) that are effective immediately. Are you sure to re-enroll the application?”
Click “Yes” if you want to proceed