CheckParticipantsAlreadyRegistered

{
  "Criteria": {
    "ActivityReservation": {
      "Activity": null,
      "DivisionId": "00000000-0000-0000-0000-000000000000",
      "Comments": null,
      "Id": "00000000-0000-0000-0000-000000000000",
      "LockTicket": null,
      "Quantity": 0,
      "OptionPrice": 0.0,
      "RuleNamesToIgnore": null,
      "Customer": null,
      "UnitPrice": 0.0,
      "ActivityParticipantReservations": null,
      "AdvancementPrice": 0.0,
      "TotalPrice": 0.0,
      "AsReseller": false,
      "Status": 0,
      "CustomerContactId": "00000000-0000-0000-0000-000000000000",
      "GroupReservations": false,
      "PromotionRuleDiscountAmount": 0.0,
      "WaiterPadDiscountPercentage": 0.0
    }
  },
  "Context": {
    "DivisionId": "00000000-0000-0000-0000-000000000000",
    "Language": "string_example",
    "ShopId": "00000000-0000-0000-0000-000000000000",
    "SessionId": "00000000-0000-0000-0000-000000000000",
    "Origin": 0,
    "Password": "string_example",
    "Encode": false,
    "AccessToken": "string_example"
  }
}

{
  "Result": {
    "ParticipantRegisteredInfos": [
      {
        "ParticipantId": "00000000-0000-0000-0000-000000000000",
        "AlreadyRegistered": false,
        "Blocking": false
      }
    ]
  }
}