runserver stopped working with aleksis-admin in Django 3.1.6

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/aleksis/core/util/manage.py", line 12, in aleksis_cmd
    execute_from_command_line(sys.argv)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/commands/runserver.py", line 61, in execute
    super().execute(*args, **options)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/base.py", line 371, in execute
    output = self.handle(*args, **options)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/commands/runserver.py", line 96, in handle
    self.run(**options)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/core/management/commands/runserver.py", line 103, in run
    autoreload.run_with_reloader(self.inner_run, **options)
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/utils/autoreload.py", line 620, in run_with_reloader
    exit_code = restart_with_reloader()
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/utils/autoreload.py", line 246, in restart_with_reloader
    args = get_child_arguments()
  File "/home/nik/Teckids/schul-frei/Entwicklung/AlekSIS/AlekSIS/apps/official/AlekSIS-Core/.venv/lib/python3.9/site-packages/django/utils/autoreload.py", line 233, in get_child_arguments
    raise RuntimeError('Script %s does not exist.' % py_script)
RuntimeError: Script aleksis-admin does not exist.