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/p16022coll624/335/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-8b1c72ff-2a14-467a-a49b-9113ca8143a7",
      "cw-3948923c-672a-4e7c-b5a2-eb8d9724e86a"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-1135c25a-83ea-4273-a73a-c43e390e9b75",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/335/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-3948923c-672a-4e7c-b5a2-eb8d9724e86a"
  }
}