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/p16022coll231/59/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-e7d4411a-5378-4669-b7ce-efc974f25a63",
      "cw-fc9661c3-08bd-40f0-b5ac-20918c00b94b"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-d33e3c8e-96f3-47cf-82e8-acb6c8c309f4",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll231/59/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-fc9661c3-08bd-40f0-b5ac-20918c00b94b"
  }
}