Roadmap Item Milestones not Showing up

[xuwang]

With UI Builder on Vancouver, to configure a roadmap component with JSON data. The roadmap milestones did show up, but the item milestones which associated with some item by ID did not show up. Any help/hint would be appreciated. Roadmap and item milestone data and meta data attached.

{
    "roadmapMilestones": [
        {
            "dueDate": {
                "displayValue": "2025-07-01 08:00:00",
                "value": "2025-07-01 08:00:00"
            },
            "id": {
                "displayValue": "M0_1",
                "value": "M0_1"
            },
            "name": {
                "displayValue": "Roadmap M1",
                "value": "Roadmap M1"
            },
            "state": {
                "displayValue": "Missed",
                "value": "Missed"
            },
            "type": {
                "displayValue": "Key Event1",
                "value": "key_event"
            }
        },
        {
            "dueDate": {
                "displayValue": "2026-07-01 08:00:00",
                "value": "2026-07-01 08:00:00"
            },
            "id": {
                "displayValue": "M0_2",
                "value": "M0_2"
            },
            "name": {
                "displayValue": "Roadmap M2",
                "value": "Roadmap M2"
            },
            "state": {
                "displayValue": "Upcoming",
                "value": "Upcoming"
            },
            "type": {
                "displayValue": "Key Event2",
                "value": "key_event"
            }
        }
    ],
    "roadmapItemMilestones": [
        {
            "A20": [
                {
                    "dueDate": {
                        "displayValue": "2023-07-01 08:00:00",
                        "value": "2023-07-01 08:00:00"
                    },
                    "id": {
                        "displayValue": "M1_1",
                        "value": "M1_1"
                    },
                    "name": {
                        "displayValue": "CHRIS Interface Migration",
                        "value": "CHRIS Interface Migration"
                    },
                    "state": {
                        "displayValue": "Upcoming",
                        "value": "Upcoming"
                    },
                    "type": {
                        "displayValue": "Key Event",
                        "value": "key_event"
                    }
                }
            ]
        }
    ]
}

{
    "type": {
         "deadline": {
              "icon": "flag-fill"
         },
         "key_milestone": {
              "icon": "diamond-fill"
         },
         "key_event": {
              "icon": "flag-fill"
         },
         "launch_date": {
              "icon": "rocket-fill"
         },
         "important_date": {
              "icon": "star-fill"
         }
    }
}