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/p16022coll230/2688/manifest.json",
    "isFetching": false
  },
  "window": {
    "collectionIndex": 0,
    "companionAreaOpen": true,
    "companionWindowIds": [
      "cw-6ba0f1ae-05a8-49b1-ad8c-d329e15d4fcc",
      "cw-2dcd2658-3263-43e6-9b72-959eff3b5ead"
    ],
    "draggingEnabled": true,
    "highlightAllAnnotations": false,
    "id": "window-079c09b8-374e-4d38-a2dc-f3d4235efd56",
    "manifestId": "https://cdm16022.contentdm.oclc.org/iiif/info/p16022coll230/2688/manifest.json",
    "maximized": false,
    "rangeId": null,
    "rotation": null,
    "selectedAnnotations": {},
    "sideBarOpen": false,
    "sideBarPanel": "info",
    "thumbnailNavigationId": "cw-2dcd2658-3263-43e6-9b72-959eff3b5ead"
  }
}