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/p16022coll230/3788/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-52d1a96c-38c5-4c04-9156-b198095ff8be",
      "cw-6e781d21-e03a-473b-aaf1-ba8eccf6c56f"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-d868adee-89fe-43ee-95ba-f270d04380c2",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/3788/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-6e781d21-e03a-473b-aaf1-ba8eccf6c56f"
  }
}