<RSAKeyValue><Modulus>2+VvfVJXR7JUmg65U/njAelZisE2LyEP7JGVVn38COECz++uhviKs+MAr6eB5LROwTd4GaZFj6WefO8FAw8sY16hIsrXn2wvA8r4+FoXsVoyUtt7ifbx7rAARTrGljaYi0CLnbktSg1+A6Rf50nAuJmTIBsFbFl7XHFT2YRvUP0=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>

byte[] modBytes = "2+VvfVJXR7JUmg65U/njAelZisE2LyEP7JGVVn38COECz++uhviKs+MAr6eB5LROwTd4GaZFj6WefO8FAw8sY16hIsrXn2wvA8r4+FoXsVoyUtt7ifbx7rAARTrGljaYi0CLnbktSg1+A6Rf50nAuJmTIBsFbFl7XHFT2YRvUP0=".getBytes(StandardCharsets.UTF_8);
        byte[] expBytes = "AQAB".getBytes(StandardCharsets.UTF_8);

        BigInteger modules = new BigInteger(1, modBytes);
        BigInteger exponent = new BigInteger(1, expBytes);

        KeyFactory rsaFactory = KeyFactory.getInstance("RSA");

        RSAPublicKeySpec rsaKeyspec =
                new RSAPublicKeySpec(modules, exponent);
        PublicKey pk = rsaFactory.generatePublic(rsaKeyspec);

        System.out.println("----" + pk);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, pk);
        byte[] bytes = cipher.doFinal(DigestUtils.md5Hex("MyTestText".toLowerCase()).getBytes(StandardCharsets.UTF_8));

        System.out.println(Arrays.toString(bytes));

<RSAKeyValue><Modulus>2+VvfVJXR7JUmg65U/njAelZisE2LyEP7JGVVn38COECz++uhviKs+MAr6eB5LROwTd4GaZFj6WefO8FAw8sY16hIsrXn2wvA8r4+FoXsVoyUtt7ifbx7rAARTrGljaYi0CLnbktSg1+A6Rf50nAuJmTIBsFbFl7XHFT2YRvUP0=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>

void textSign() {
        byte[] modBytes = "v5JmVyqYui4Hg/D2Z+l6tkMgH6aq1O3MuKB05EhrPRifJ4gfbnGZbIuom6FnLMwiC3XM5kVvxwuesTS9lPbPmWYiDk0vjzV/UlC4XJa7tXDFOyRtzUxSWPaVvWB9A8OY0AhYFQYXNqvtql0Z4SxwYMAbzuNpolD2Mi9uEQf2v9s=".getBytes(StandardCharsets.UTF_8);
        byte[] expBytes = "AQAB".getBytes(StandardCharsets.UTF_8);

        BigInteger modules = new BigInteger(1, modBytes);
        BigInteger exponent = new BigInteger(1, expBytes);

        KeyFactory rsaFactory = KeyFactory.getInstance("RSA");

        RSAPrivateKeySpec rsaKeyspec =
                new RSAPrivateKeySpec(modules, exponent);
        PrivateKey pk = rsaFactory.generatePrivate(rsaKeyspec);

        System.out.println(sign(DigestUtils.md5Hex("myTestText".toLowerCase()), pk));
    }

    String sign(String plainText, PrivateKey privateKey) throws Exception {
        Signature privateSignature = Signature.getInstance("SHA256withRSA");
        privateSignature.initSign(privateKey);
        privateSignature.update(plainText.getBytes(StandardCharsets.UTF_8));

        byte[] signature = privateSignature.sign();
        return Arrays.toString(signature);
    }

var rsa = new RSACryptoServiceProvider();
rsa.FromXmlString(publicKey);
var dataToEncrypt = _encoder.GetBytes(data);
var encryptedByteArray = rsa.Encrypt(dataToEncrypt, false).ToArray();
var length = encryptedByteArray.Count();
var item = 0;
var sb = new StringBuilder();
foreach (var x in encryptedByteArray)
{
    item++;
    sb.Append(x);
    if (item < length)
        sb.Append(",");
}

return sb.ToString();

<RSAKeyValue><Modulus>2+VvfVJXR7JUmg65U/njAelZisE2LyEP7JGVVn38COECz++uhviKs+MAr6eB5LROwTd4GaZFj6WefO8FAw8sY16hIsrXn2wvA8r4+FoXsVoyUtt7ifbx7rAARTrGljaYi0CLnbktSg1+A6Rf50nAuJmTIBsFbFl7XHFT2YRvUP0=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>

Private token not found on server

83,-24,52,80,53,28,-47,-123,-74,116,-74,13,32,-79,84,-29,-84,-73,-71,20,101,-61,69,-110,-120,-24,106,69,-32,-63,12,127,105,44,117,-6,-14,-1,-73,-67,43,120,127,115,-33,95,-96,-7,95,-88,-14,-98,81,97,92,122,-119,92,-109,-35,-125,99,-85,-90,21,-90,95,-19,-10,108,-6,47,-13,-125,59,105,107,-69,-68,-11,-65,-75,94,-72,-93,-106,12,36,45,117,-72,45,-33,-99,-5,61,28,-65,14,103,-79,53,-71,-13,44,48,79,70,-93,-51,5,-118,124,-101,56,58,126,70,-103,56,-107,91,0,21,104,59,103,-64

 public String signData(ResponseData responseData, String methodHash) {
        RSAKeyValue rsaKeyValue = xmlToObject(responseData.getPublicKey());

        byte[] modBytes = Base64Utils.decodeFromString(rsaKeyValue.getModulus());
        byte[] expBytes = Base64Utils.decodeFromString(rsaKeyValue.getModulus());

        BigInteger modules = new BigInteger(1, modBytes);
        BigInteger exponent = new BigInteger(1, expBytes);

        KeyFactory rsaFactory = KeyFactory.getInstance("RSA");

        RSAPrivateKeySpec rsaKeySpec =
                new RSAPrivateKeySpec(modules, exponent);
        PrivateKey pk = rsaFactory.generatePrivate(rsaKeySpec);

        return sign(getMethodHash(methodHash), pk);
}


String sign(String plainText, PrivateKey privateKey) throws Exception {
        Signature privateSignature = Signature.getInstance("SHA1withRSA");
        privateSignature.initSign(privateKey);
        privateSignature.update(plainText.getBytes(StandardCharsets.UTF_16));

        byte[] signature = privateSignature.sign();
        return Arrays.toString(signature);
    }

Authorization-Token: 62,148,123,57,253,121,179,128,57,...

var encryptedByteArray = rsa.Encrypt(dataToEncrypt, false).ToArray();