CVAT COCO json file segmentation empty

Question

I'm finished my annotations and Export task Dataset by coco 1.0version.

Downloaded coco file and check json file, my segmentation part is all empty

This is one of my example result.

{"licenses": [{"name": "", "id": 0, "url": ""}], "info": {"contributor": "", "date_created": "", "description": "", "url": "", "version": "", "year": ""}, "categories": [{"id": 1, "name": "HolePairLeft", "supercategory": ""}, {"id": 2, "name": "HolePairRight", "supercategory": ""}, {"id": 3, "name": "ACHole", "supercategory": ""}], "images": [{"id": 1, "width": 2048, "height": 1536, "file_name": "IONIQ5_Black_2021_LC3_WP_color204.png"

"annotations": [{"id": 1, "image_id": 1, "category_id": 3, **"segmentation": []**, "area": 16373.05619999998, "bbox": [824.1, 1305.45, 131.86, 124.17], "iscrowd": 0, "attributes": {"occluded": false}}, {"id": 2, "image_id": 1, "category_id": 1, **"segmentation": []**, "area": 1713.5814999999943, "bbox": [828.83, 1468.64, 57.95, 29.57], "iscrowd": 0, "attributes": {"occluded": false}}, {"id": 3, "image_id": 1, "category_id": 2, **"segmentation": []**, "area": 2955.6654000000044, "bbox": [904.51, 1465.1, 56.17, 52.62], "iscrowd": 0, "attributes": {"occluded": false}}

This is my annotation task example

My bbox lists exist already, but why my segmentation lists box empty?