Extrinsic 12988-1

{
  "heartbeat": {
    "blockNumber": 12986,
    "sessionIndex": 216,
    "validatorsLen": 4,
    "authorityIndex": 0
  },
  "signature": "0xb0365bb78225af83c053cc5cf7b89c510c7cdd44b2d3b187f2984b0f348dd57fc197c23e1bdf2e3e3633dc04a15055b2cc0a2a8f79d8b38fae2358645fbcad8b"
}