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/p16022coll246/229/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-b0fee64c-fae1-45f2-81a4-b2ae1c1c9bda",
      "cw-90fd0876-aa11-46ab-a10f-c63309296bf6"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-19ce116a-cbc9-4489-9177-5ae60b6c1d14",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/229/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-90fd0876-aa11-46ab-a10f-c63309296bf6"
  }
}