Are you currently a student of the University of Antwerp?
Then you use the request "Re-enrolment 2020-2021" in your SisA self service to re-enrol. The instructions can be found in the helpdesk.
Re-enrolment is possible between 22 July and 14 October 2020. Please note that the faculty can limit your course list if you re-enrol after 1 October.