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/p16022coll231/2160/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-f59813c9-5db5-4aae-a3d0-2d5a2d68e073",
      "cw-3b6e4a34-ad6f-43d6-a746-da60b99c7b44"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-5772e8e9-908d-42d8-a081-63738bddb272",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll231/2160/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-3b6e4a34-ad6f-43d6-a746-da60b99c7b44"
  }
}