{
  "manageEntity": {
    "action": "Save",
    "entityId": "1621549805",
    "entityType": "Track",
    "nonce": "0x741f01a9af6b1d8a20b11491df325cfc6305ddec2f33513c9bcbac54efa9701c",
    "signature": "0x28b2a052e5cce1df4758703c61be1fcb192f7622dc3f8034bcb47814a0ce800e6cf170e80592b6b1acd49b1946dacf28d6f819cee1d2ee147f4f22e8f14ed5a01b",
    "signer": "0x40aE1C539711FBaE3930131b028D9c764fD8EaCb",
    "userId": "35251"
  }
}