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/p16022coll230/1690/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-92bdb172-1173-443d-9ba0-f020f34b73d8",
      "cw-f890e638-f44c-40bc-a1ad-6af685dbe45b"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-787f6cc7-90c2-4068-b73e-215085a642d8",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/1690/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-f890e638-f44c-40bc-a1ad-6af685dbe45b"
  }
}