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/p16022coll624/512/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-7c543706-f1d8-4655-bfc8-f6324c19f4d2",
      "cw-d6078453-d5e0-4db0-9899-28ee874e245f"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-4162482b-75e6-4983-b72a-861f6ce328f7",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/512/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-d6078453-d5e0-4db0-9899-28ee874e245f"
  }
}