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/p16022coll624/481/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-a60f99d1-46f4-4f92-a1c1-5d39e8d8a656",
      "cw-9c3da3d4-be9e-4130-b916-4d34281c078d"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-e230ddbe-e916-4b76-98de-5049252c7e45",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/481/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-9c3da3d4-be9e-4130-b916-4d34281c078d"
  }
}