I am getting "{"Object reference not set to an instance of an object."}" execption.
I am using below code to generate byte array in der format
public static byte[] BouncyPrivateKeyParametersToPkcs8()
{
SecureRandom secureRandom = new SecureRandom();
var keygenParam = new KeyGenerationParameters(secureRandom, 521);
var keyGenerator = new ECKeyPairGenerator();
keyGenerator.Init(keygenParam);
AsymmetricKeyParameter key = keyGenerator.GenerateKeyPair().Private;
var bcPrivateKeyInfo = Org.BouncyCastle.Pkcs.PrivateKeyInfoFactory.CreatePrivateKeyInfo(key);
byte[] stream = bcPrivateKeyInfo.GetDerEncoded();
return stream;
}