Extrinsic 13521-2

{
  "heartbeat": {
    "blockNumber": 13520,
    "sessionIndex": 225,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x06e1401550b4a14640390e9d37598fdbce29bf23ec011922f572d6e748da8b23364a293a48dd89ef4869d9266d48e6d583f85efc5d3284b73a9352e143400f87"
}