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/p16022coll246/222/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-196e4d08-d413-4cb8-a9d1-efa767f69b33",
      "cw-603170eb-80cd-4016-9b08-7459a43c64ee"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-afe308fe-1a40-42d5-94d5-5ff317a0cfc6",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/222/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-603170eb-80cd-4016-9b08-7459a43c64ee"
  }
}