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/p16022coll230/443/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-ea2cbb35-f96a-48d6-8885-95798626b8cc",
      "cw-8da107f4-bdfd-4e46-924c-f308acff00a3"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-cc174d73-0781-435d-8ff3-465db559a00d",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/443/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-8da107f4-bdfd-4e46-924c-f308acff00a3"
  }
}