Mirador viewer

SyntaxError: Unexpected token '<', "<!DOCTYPE "... is not valid JSON

{
  "manifest": {
    "error": "SyntaxError: Unexpected token '<', \"<!DOCTYPE \"... is not valid JSON",
    "id": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/414/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-b5752bc5-1432-472b-9212-907f48938cb4",
      "cw-f51aae5a-04ce-47e0-947b-0e28c4354472"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-91a2706e-761a-421d-b25f-8aa272058a21",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/414/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-f51aae5a-04ce-47e0-947b-0e28c4354472"
  }
}