diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiCrypto.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiCrypto.java
index fbd395cdf..c82bcf82c 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiCrypto.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiCrypto.java
@@ -119,7 +119,11 @@ public class HuaweiCrypto {
                                                 .put(message)
                                                 .array();
         byte[] digestStep1 = CryptoUtils.calcHmacSha256(msgToDigest, nonce);
-        return CryptoUtils.calcHmacSha256(digestStep1, nonce);
+        byte[] challenge = ByteBuffer.allocate(0x40)
+                .put(CryptoUtils.calcHmacSha256(digestStep1, nonce))
+                .put(digestStep1)
+                .array();
+        return challenge;
     }
 
     public byte[] computeDigestHiChainLite(byte[] message, byte[] key, byte[] nonce) throws NoSuchAlgorithmException, InvalidKeyException, InvalidKeySpecException, UnsupportedEncodingException {
@@ -138,7 +142,11 @@ public class HuaweiCrypto {
         } else {
             digestStep1 = CryptoUtils.calcHmacSha256(msgToDigest, nonce);
         }
-        return CryptoUtils.calcHmacSha256(digestStep1, nonce);
+        byte[] challenge = ByteBuffer.allocate(0x40)
+                .put(CryptoUtils.calcHmacSha256(digestStep1, nonce))
+                .put(digestStep1)
+                .array();
+        return challenge;
     }
 
     public byte[] digestChallenge(byte[] secretKey, byte[] nonce) throws NoSuchAlgorithmException, InvalidKeyException, InvalidKeySpecException, UnsupportedEncodingException {
@@ -150,7 +158,11 @@ public class HuaweiCrypto {
                         .put(secretKey)
                         .put(MESSAGE_CHALLENGE)
                         .array();
-                return CryptoUtils.calcHmacSha256(key, nonce);
+                byte[] challenge = ByteBuffer.allocate(0x40)
+                        .put(CryptoUtils.calcHmacSha256(key, nonce))
+                        .put(key)
+                        .array();
+                return challenge;
             }
             return computeDigestHiChainLite(MESSAGE_CHALLENGE, secretKey, nonce);
         }
@@ -166,7 +178,11 @@ public class HuaweiCrypto {
                         .put(secretKey)
                         .put(MESSAGE_RESPONSE)
                         .array();
-                return CryptoUtils.calcHmacSha256(key, nonce);
+                byte[] challenge = ByteBuffer.allocate(0x40)
+                        .put(CryptoUtils.calcHmacSha256(key, nonce))
+                        .put(key)
+                        .array();
+                return challenge;
             }
             return computeDigestHiChainLite(MESSAGE_RESPONSE, secretKey, nonce);
         }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiPacket.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiPacket.java
index 3c5c56972..b7c0ba3c1 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiPacket.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiPacket.java
@@ -58,6 +58,7 @@ public class HuaweiPacket {
         protected byte interval;
         protected byte authAlgo;
         protected byte encryptMethod;
+        protected byte[] firstKey;
 
         public void setAuthVersion(byte authVersion) {
             this.authVersion = authVersion;
@@ -153,6 +154,14 @@ public class HuaweiPacket {
         public byte getEncryptMethod () {
             return this.encryptMethod;
         }
+
+        public void setFirstKey(byte[] firstKey) {
+            this.firstKey = firstKey;
+        }
+
+        public byte[] getFirstKey() {
+            return firstKey;
+        }
     }
 
     public static abstract class ParseException extends Exception {
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/requests/GetAuthRequest.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/requests/GetAuthRequest.java
index 9c252fe20..15f7445ce 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/requests/GetAuthRequest.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huawei/requests/GetAuthRequest.java
@@ -74,8 +74,13 @@ public class GetAuthRequest extends Request {
                     .putShort(authVersion)
                     .put(clientNonce)
                     .array();
-            byte[] challenge = huaweiCrypto.digestChallenge(key, doubleNonce);
+            ByteBuffer digestedChallenge = ByteBuffer.wrap(huaweiCrypto.digestChallenge(key, doubleNonce));
+            byte[] challenge = new byte[0x20];
+            digestedChallenge.get(challenge, 0x00, 0x20);
             LOG.debug("challenge: " + GB.hexdump(challenge));
+            byte[] firstKey = new byte[0x10];
+            digestedChallenge.get(firstKey, 0x00, 0x10);
+            paramsProvider.setFirstKey(firstKey);
             if (challenge == null)
                 throw new RequestCreationException("Challenge null");
             return new DeviceConfig.Auth.Request(paramsProvider, challenge, nonce).serialize();
@@ -94,7 +99,10 @@ public class GetAuthRequest extends Request {
             throw new ResponseTypeMismatchException(receivedPacket, DeviceConfig.Auth.Response.class);
 
         try {
-            byte[] expectedAnswer = huaweiCrypto.digestResponse(key, doubleNonce);
+            ByteBuffer digestedChallenge = ByteBuffer.wrap(huaweiCrypto.digestResponse(key, doubleNonce));
+            byte[] expectedAnswer = new byte[0x20];
+            digestedChallenge.get(expectedAnswer, 0x00, 0x20);
+            LOG.debug("challenge: " + GB.hexdump(expectedAnswer));
             if (expectedAnswer == null)
                 throw new ResponseParseException("Challenge null");
             byte[] actualAnswer = ((DeviceConfig.Auth.Response) receivedPacket).challengeResponse;