{
  "manageEntity": {
    "action": "Save",
    "entityId": "904784520",
    "entityType": "Track",
    "nonce": "0xc190e4f21abf14906241bfa17741ef69f65e5ba2efc381d61bc88a2e996939bb",
    "signature": "0x57922b6b09a2f949324f0d2aeb6e78d0a1227b3618576cdfa7736dc853ae5cfc231d623e9fa13dcf8b6645b7c7fd08ac5e9bc8051c68c9c9a475c3aaaf334df41c",
    "signer": "0x243A439c272133AEEE0073AF4986dE391C430866",
    "userId": "77551267"
  }
}