Error message

• Notice: Trying to get property of non-object in theme_gri_element_list() (line 281 of /var/www/installazioni_bilanci/sea/sea15csr-drupal-7.56-2017-10-06/sites/sea15csr/modules/custom/msg_gri/msg_gri.module).
• Notice: Trying to get property of non-object in theme_gri_element_list() (line 281 of /var/www/installazioni_bilanci/sea/sea15csr-drupal-7.56-2017-10-06/sites/sea15csr/modules/custom/msg_gri/msg_gri.module).