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/p16022coll231/49/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-c1619d15-ab42-44a2-b14d-c089c5a75af1",
      "cw-4c052dd2-168f-4a56-8783-eb702f6e5db2"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-057ebe87-b6ef-4667-9fd8-81e4844fd9ec",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll231/49/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-4c052dd2-168f-4a56-8783-eb702f6e5db2"
  }
}