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/p16022coll246/397/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-766bd128-8bd6-4c3e-b8a8-4947ea5228b6",
      "cw-43215aea-4279-4631-9cca-660cfdf6e509"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-d54dc2e8-febb-4e34-b21a-c9c4280513b0",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/397/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-43215aea-4279-4631-9cca-660cfdf6e509"
  }
}