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/p16022coll624/249/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-051fbe9a-771a-4748-b777-9805969f8c7e",
      "cw-85140e5e-9deb-401c-9393-d27da1b5ea24"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-3e7db5c0-9faa-4aa6-8b80-1079ccc67be2",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/249/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-85140e5e-9deb-401c-9393-d27da1b5ea24"
  }
}