Extrinsic 7720-1

{
  "heartbeat": {
    "blockNumber": 7719,
    "sessionIndex": 128,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x82349b761b7ba798d2beec5a9aa5748a7780b72c59448f304b8990db25c2db16e974af7ac7281b22a2f07e98905731ee4e9c51569f64466714dcb767f3713385"
}