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/p16022coll231/18/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-5a1e0e6a-89cf-4a78-922b-e7fef873c85f",
      "cw-dc8a8b63-e544-4b7f-b81b-623c91efd559"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-f62d86ee-66b6-4f7a-b66b-1f9aa01414cc",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll231/18/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-dc8a8b63-e544-4b7f-b81b-623c91efd559"
  }
}