General help

In stack trace, I got these errors:
line 497 of /lib/dml/moodle_database.php: dml_write_exception thrown
line 293 of /lib/dml/moodle_read_slave_trait.php: call to moodle_database->query_end()
line 1362 of /lib/dml/mysqli_native_moodle_database.php: call to mysqli_native_moodle_database->query_end()
line 1408 of /lib/dml/mysqli_native_moodle_database.php: call to mysqli_native_moodle_database->insert_record_raw()
line 1271 of /backup/util/dbops/restore_dbops.class.php: call to mysqli_native_moodle_database->insert_record()
line 1146 of /backup/moodle2/restore_stepslib.php: call to restore_dbops::create_included_users()
line 34 of /backup/util/plan/restore_execution_step.class.php: call to restore_create_included_users->define_execution()
line 181 of /backup/util/plan/base_task.class.php: call to restore_execution_step->execute()
line 191 of /backup/util/plan/base_plan.class.php: call to base_task->execute()
line 168 of /backup/util/plan/restore_plan.class.php: call to base_plan->execute()
line 408 of /backup/controller/restore_controller.class.php: call to restore_plan->execute()
line 219 of /backup/util/ui/restore_ui.class.php: call to restore_controller->execute_plan()
line 146 of /backup/restore.php: call to restore_ui->execute()