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/p16022coll229/1819/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-f875cc57-6e1c-4b35-8576-d3f41f8a1f2a",
      "cw-a449b811-04d9-4fe1-a6f7-b7195c430df8"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-4a55d0a8-bcbc-4408-bc81-cee9fb63c330",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll229/1819/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-a449b811-04d9-4fe1-a6f7-b7195c430df8"
  }
}