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/p16022coll624/464/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-88ac803c-7f8f-4c96-a5d7-8eef6a644207",
      "cw-a52b13bf-53d1-4317-a781-80dfe5cf2a13"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-da268c0b-887a-409c-bff6-221f63ea1e09",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/464/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-a52b13bf-53d1-4317-a781-80dfe5cf2a13"
  }
}