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/p16022coll246/414/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-c9194b56-eb2c-44f8-964c-10ce77fb93c4",
      "cw-5c644654-3f5d-4638-97c6-c3eadbaf4137"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-18ed740f-72ea-4b3c-a510-9f7cd34c903b",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/414/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-5c644654-3f5d-4638-97c6-c3eadbaf4137"
  }
}