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/p16022coll246/320/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-43e30539-04bd-47f2-8c68-d7ece1f60c64",
      "cw-56383faf-0fd1-4ae9-9c07-cf0fee94eaa0"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-509dab97-075e-4a2f-bc9b-af3f28aca400",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll246/320/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-56383faf-0fd1-4ae9-9c07-cf0fee94eaa0"
  }
}