ECD retuns an error on some locations

The error is:

Internal Server Error: /ecd/location/7803
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/django/core/handlers/base.py", line 115, in get_response
    response = callback(request, *callback_args, **callback_kwargs)
  File "/usr/lib/python2.7/dist-packages/django/views/generic/base.py", line 68, in view
    return self.dispatch(request, *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/openquakeplatform/gemecdwebsite/location/location.py", line 309, in dispatch
    casualtyMatrixDisplayArr[inventoryClassesList.index(survey_record.inventoryclassid_id)][casualtyLevelsList.index(survey_record.damagelevelid_id)] = {'cell':surveyfields, 'id': survey_record.id }
ValueError: 0 is not in list