Course restore error when gradinging guide used - mdl_gradingform_guide_fillings dup key

When attempting to restore a course in which grading guide is used for assignments, consistently receive an error, log entry below:

Default exception handler: Error writing to database Debug: Duplicate entry '133-0' for key 'mdl_gradguidfill_inscri_uix'
INSERT INTO mdl_gradingform_guide_fillings (criterionid,remark,remarkformat,score,instanceid) VALUES(?,?,?,?,?)
[array (
  0 => 0,
  1 => '',
  2 => '0',
  3 => '0.00000',
  4 => 133,
)]
Error code: dmlwriteexception
* line 489 of /lib/dml/moodle_database.php: dml_write_exception thrown
* line 1329 of /lib/dml/mysqli_native_moodle_database.php: call to moodle_database->query_end()
* line 1375 of /lib/dml/mysqli_native_moodle_database.php: call to mysqli_native_moodle_database->insert_record_raw()
* line 133 of /grade/grading/form/guide/backup/moodle2/restore_gradingform_guide_plugin.class.php: call to mysqli_native_moodle_database->insert_record()
* line 137 of /backup/util/plan/restore_structure_step.class.php: call to restore_gradingform_guide_plugin->process_gradinform_guide_filling()
* line 112 of /backup/util/helper/restore_structure_parser_processor.class.php: call to restore_structure_step->process()
* line 178 of /backup/util/xml/parser/processors/grouped_parser_processor.class.php: call to restore_structure_parser_processor->dispatch_chunk()
* line 100 of /backup/util/helper/restore_structure_parser_processor.class.php: call to grouped_parser_processor->postprocess_chunk()
* line 148 of /backup/util/xml/parser/processors/simplified_parser_processor.class.php: call to restore_structure_parser_processor->postprocess_chunk()
* line 92 of /backup/util/xml/parser/processors/progressive_parser_processor.class.php: call to simplified_parser_processor->process_chunk()
* line 190 of /backup/util/xml/parser/progressive_parser.class.php: call to progressive_parser_processor->receive_chunk()
* line 278 of /backup/util/xml/parser/progressive_parser.class.php: call to progressive_parser->publish()
* line ? of unknownfile: call to progressive_parser->end_tag()
* line 179 of /backup/util/xml/parser/progressive_parser.class.php: call to xml_parse()
* line 158 of /backup/util/xml/parser/progressive_parser.class.php: call to progressive_parser->parse()
* line 110 of /backup/util/plan/restore_structure_step.class.php: call to progressive_parser->process()
* line 181 of /backup/util/plan/base_task.class.php: call to restore_structure_step->execute()
* line 210 of /backup/moodle2/restore_activity_task.class.php: call to base_task->execute()
* line 178 of /backup/util/plan/base_plan.class.php: call to restore_activity_task->execute()
* line 167 of /backup/util/plan/restore_plan.class.php: call to base_plan->execute()
* line 339 of /backup/controller/restore_controller.class.php: call to restore_plan->execute()
* line 224 of /backup/util/ui/restore_ui.class.php: call to restore_controller->execute_plan()
* line 135 of /backup/restore.php: call to restore_ui->execute()