Extrinsic 21499-1

{
  "heartbeat": {
    "blockNumber": 21497,
    "sessionIndex": 358,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0x962cdde3deaad2ac431042987d0dd8d12d7e8ceb140c384772ae121dabb8c022920b006964a488e884f804e0912298e9f03e3030c2b187a0c1b5e52993cd5d8b"
}