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/p16022coll229/5297/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-0b9ce808-2273-4bd0-9123-da0b3dc67a1b",
      "cw-e5e5d199-fa56-4a3e-af20-f808d70ece63"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-fa83b882-cf52-4772-af5f-1834264ff60f",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll229/5297/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-e5e5d199-fa56-4a3e-af20-f808d70ece63"
  }
}