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/p16022coll230/2519/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-110b7da4-d938-445f-8acc-c4cd506f40b8",
      "cw-c4139b00-728a-4801-b6e7-9aff1a5817bf"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-16007e04-9a2d-4242-ac08-897bb33e707f",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/2519/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-c4139b00-728a-4801-b6e7-9aff1a5817bf"
  }
}