Admin throws an error for thumbnail

[danieleguido]

ERROR 2024-10-09 09:06:43,380 - django.request L241: Internal Server Error: /admin/miller/document/
Traceback (most recent call last):
File "/usr/local/lib/python3.8/site-packages/django/db/models/options.py", line 668, in get_field
return self.fields_map[field_name]
KeyError: 'thumbnail'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/local/lib/python3.8/site-packages/django/contrib/admin/utils.py", line 271, in lookup_field
f = _get_non_gfk_field(opts, name)
File "/usr/local/lib/python3.8/site-packages/django/contrib/admin/utils.py", line 302, in _get_non_gfk_field
field = opts.get_field(name)
File "/usr/local/lib/python3.8/site-packages/django/db/models/options.py", line 670, in get_field
raise FieldDoesNotExist(
django.core.exceptions.FieldDoesNotExist: Document has no field named 'thumbnail'