Patch 1

src/main/java/com/binance/api/client/security/HmacSHA256Signer.java

@@ -21,7 +21,7 @@ public static String sign(String message, String secret) {
       Mac sha256_HMAC = Mac.getInstance("HmacSHA256");
       SecretKeySpec secretKeySpec = new SecretKeySpec(secret.getBytes(), "HmacSHA256");
       sha256_HMAC.init(secretKeySpec);
-      return Hex.encodeHexString(sha256_HMAC.doFinal(message.getBytes()));
+      return new String(Hex.encodeHex(sha256_HMAC.doFinal(message.getBytes())));
     } catch (Exception e) {
       throw new RuntimeException("Unable to sign message.", e);
     }