{
  "$ref": "core/event.json",
  "type": "m.room_key.withheld",
  "content": {
    "algorithm": "m.megolm.v1.aes-sha2",
    "room_id": "!Cuyf34gef24t:localhost",
    "session_id": "X3lUlvLELLYxeTx4yOVu6UDpasGEVO0Jbu+QFnm0cKQ",
    "sender_key": "RF3s+E7RkTQTGF2d8Deol0FkQvgII2aJDf3/Jp5mxVU",
    "code": "m.unverified",
    "reason": "Device not verified"
  }
}