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/p16022coll624/246/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-db533fac-d749-48e8-9d9c-580f4201aa1a",
      "cw-eb745654-2c66-42e0-81c0-059d07d9e004"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-2a143860-80da-45c9-a6b6-c007be062c68",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll624/246/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-eb745654-2c66-42e0-81c0-059d07d9e004"
  }
}