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/p16022coll230/733/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-695fabaf-c379-4203-a387-53a8a37567b5",
      "cw-b4081b49-f6ae-4faa-bd50-944929ddb5ae"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-212ce7ef-f5cd-499d-9f43-672dc01c5646",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/733/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-b4081b49-f6ae-4faa-bd50-944929ddb5ae"
  }
}