/othersonbs/kml: <' not supported between instances of 'NoneType' and 'float'

[aptiko]

Traceback (most recent call last):
  File "/opt/naturebank/venv/lib/python3.9/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/opt/naturebank/venv/lib/python3.9/site-packages/django/core/handlers/base.py", line 181, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/opt/naturebank/naturebank/views.py", line 299, in kml
    if arow.gis_area < areatrigger:

Exception Type: TypeError at /othersonbs/kml/
Exception Value: '<' not supported between instances of 'NoneType' and 'float'