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/p16022coll246/369/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-a1ec8912-5bda-4468-a732-cc5fb6c57b07",
      "cw-a101f1ae-6585-4945-b6d7-4d5887b7ce48"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-1112e031-bcdf-47ac-a730-198cc1744e7d",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/369/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-a101f1ae-6585-4945-b6d7-4d5887b7ce48"
  }
}