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/p16022coll624/931/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-e9c74af9-97bb-4f6c-a579-c1c6224b3148",
      "cw-45c732f1-7984-424d-a577-3e29a3ad24de"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-e7f246b6-8bad-4bed-b592-2b9045cf3cf5",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/931/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-45c732f1-7984-424d-a577-3e29a3ad24de"
  }
}