Extrinsic 21309-1

{
  "heartbeat": {
    "blockNumber": 21307,
    "sessionIndex": 355,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0xe670133830340205ea68cf93ee761fa46553d9ea82c0c07eb3e6a967c9dc01571b3ebbe2b5e19d875d197631fb95823732a8043993b81ff4f02b39a766a8478e"
}