C# MercadoPago SDK：错误 400 |请求数据无效

Question

我正在使用 MercadoPago SDK 并尝试创建 PreapprovalCreateRequest 但我收到此错误：

Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware：错误：执行请求时发生未处理的异常。

MercadoPago.Error.MercadoPagoApiException：API 响应错误。 |状态码：400 | API 消息：请求数据无效

这是我目前使用的代码：

PreapprovalCreateRequest paymentRequest = new PreapprovalCreateRequest
{
    ExternalReference = codPagamento.ToString(),
    BackUrl = (siteAddress) + "/api/public/mercado-pago-webhook",
    PayerEmail = usuario.Email,
    Reason = "Teste Assinatura",
    Status = "authorized",
    AutoRecurring = new PreApprovalAutoRecurringCreateRequest
    {
         CurrencyId = "BRL",
         Frequency = 1,
         FrequencyType = "months",
         TransactionAmount = pagamento.ValorBruto,
    }
};

var requestOptions = new RequestOptions
{
    AccessToken = mercadoPagoAccessToken
};

var payment = await new PreapprovalClient().CreateAsync(paymentRequest, requestOptions);