const options = {
  method: 'PATCH',
  headers: {
    'x-organization-id': '<x-organization-id>',
    'x-api-key': '<api-key>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({corrections: [{row_index: 123, column: '<string>', value: '<unknown>'}]})
};

fetch('https://api.dcycle.io/v2/imports/{import_id}/rows', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "total_errors_remaining": 123,
  "updated_rows": [
    {
      "row_index": 123,
      "data": {},
      "errors": {}
    }
  ]
}