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/p16022coll624/909/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-6b85353b-6ad7-4cca-af19-01e62a9906e2",
      "cw-b683a320-1338-4a83-a3cf-bd0714f292d4"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-bf0bfa42-3f8d-435e-aaca-d6bdf062908d",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/909/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-b683a320-1338-4a83-a3cf-bd0714f292d4"
  }
}