How can I clear date value via bulk edit api ?

Hi Thinh Le,

Did you try omitting the formattedDate property entirely or explicitly setting the date object to null?

{
  "editedFieldsInput": {
    "datePickerFields": [
      {
        "fieldId": "duedate",
        "date": null
      }
    ]
},
   "selectedActions": ["duedate"],
   "selectedIssueIdsOrKeys": ["10309"],
   "sendBulkNotification": false
}