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/p16022coll230/2512/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-aeba3ec6-020f-461b-8619-72bc2fb3ea40",
      "cw-4e0c9e92-21ff-4ca6-8926-377176c54585"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-23f34658-6dee-479b-9bff-416ae7f0d025",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/2512/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-4e0c9e92-21ff-4ca6-8926-377176c54585"
  }
}