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/p16022coll246/90/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-69373431-875a-4c9d-b20f-a6a2de348bdb",
      "cw-b0a92607-05a8-4a6b-8d9a-ca7da161fe9f"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-bfac8c21-56a3-4cc3-9e34-d744bf174e4d",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/90/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-b0a92607-05a8-4a6b-8d9a-ca7da161fe9f"
  }
}