AsymmetricCipherKeyPair issuerKeyPair=null;
if (issuerCertificate.HasCngKey())
{
   var cngPrivateKey = issuerCertificate.GetCngPrivateKey();
   var rsa = new RSACng(cngPrivateKey);

   issuerKeyPair = DotNetUtilities.GetKeyPair(privateKey);
}

System.ArgumentException: Unsupported algorithm specified
Parameter name: privateKey
   at Org.BouncyCastle.Security.DotNetUtilities.GetKeyPair(AsymmetricAlgorithm privateKey)
   at Statoil.PleaseInspect.Sap.Services.CertificateGeneratorService.IssueCertificate(String subjectName, X509Certificate2 issuerCertificate, String[] subjectAlternativeNames, KeyPurposeID[] usages) in C:APPLdevmad-pleaseinspect-authservicesrcStatoil.PleaseInspect.SapServicesCertificateGeneratorService.cs:line 70