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/p16022coll246/288/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-9778c8d1-ad6e-4d42-9a5b-2172e6f74cf0",
      "cw-38707fb4-9352-4da9-817f-613a770c2249"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-3f6ca1be-a645-4fa9-a335-3b9ab75e106f",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/288/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-38707fb4-9352-4da9-817f-613a770c2249"
  }
}