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-7d1ad90f-29bb-4938-987b-3026ce300f10",
      "cw-5e377d00-9dd9-4d6e-9f4a-6ace4755c727"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-5a8f81ca-b4a3-4cf0-9e3e-d29cd5512f11",
    "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-5e377d00-9dd9-4d6e-9f4a-6ace4755c727"
  }
}