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/p16022coll246/367/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-9cb97468-1a97-4ee6-92d0-4dbf347300e8",
      "cw-dccad82d-1681-40ad-923a-f836f5936ba4"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-c5389275-5083-44ca-ba3b-24abf62ee7bd",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/367/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-dccad82d-1681-40ad-923a-f836f5936ba4"
  }
}