diff --git a/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoService.java b/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoService.java
index d127570e..8d615715 100644
--- a/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoService.java
+++ b/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoService.java
@@ -2,8 +2,10 @@ package vip.mate.auth.sso;
 
 import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
 import com.baomidou.mybatisplus.core.conditions.update.LambdaUpdateWrapper;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.dao.DuplicateKeyException;
 import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
 import org.springframework.stereotype.Service;
@@ -46,9 +48,9 @@ public class SsoService {
     private final AuthService authService;
     private final SsoProperties ssoProperties;
     private final BCryptPasswordEncoder passwordEncoder;
-    private final com.fasterxml.jackson.databind.ObjectMapper objectMapper;
+    private final ObjectMapper objectMapper;
     /** Optional — audit may be null in narrow test contexts. */
-    @org.springframework.beans.factory.annotation.Autowired(required = false)
+    @Autowired(required = false)
     private AuditEventService auditService;
 
     // ==================== authorize ====================
@@ -228,6 +230,16 @@ public class SsoService {
                         503, "SSO 登录遇到并发冲突, 请重试");
             }
             return createSsoUser(providerId, info, true);
+        } catch (RuntimeException e) {
+            // Identity insert failed for a non-duplicate reason (e.g. transient DB error).
+            // The two inserts are not in a shared transaction — this method is self-invoked
+            // and the enclosing callback performs a network call, so a method-level
+            // @Transactional would not apply. Roll back the freshly inserted user here so we
+            // never leave a passwordless orphan account behind.
+            if (newUser.getId() != null) {
+                userMapper.deleteById(newUser.getId());
+            }
+            throw e;
         }
     }
 
@@ -240,7 +252,7 @@ public class SsoService {
     private void audit(String action, String provider, String externalId, Long userId) {
         if (auditService != null) {
             try {
-                String detail = objectMapper.writeValueAsString(java.util.Map.of(
+                String detail = objectMapper.writeValueAsString(Map.of(
                         "provider", provider != null ? provider : "",
                         "userId", userId != null ? userId : "null"));
                 auditService.record(action, "sso",
diff --git a/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoStateService.java b/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoStateService.java
index 27139fa7..00e1e8ea 100644
--- a/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoStateService.java
+++ b/mateclaw-server/src/main/java/vip/mate/auth/sso/SsoStateService.java
@@ -8,6 +8,7 @@ import io.jsonwebtoken.security.Keys;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.dao.DuplicateKeyException;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Service;
 import vip.mate.auth.sso.model.SsoStateEntity;
@@ -15,10 +16,12 @@ import vip.mate.auth.sso.provider.SsoUserInfo;
 import vip.mate.auth.sso.repository.SsoStateMapper;
 import vip.mate.exception.MateClawException;
 
+import javax.crypto.Mac;
 import javax.crypto.SecretKey;
 import java.nio.charset.StandardCharsets;
 import java.time.LocalDateTime;
 import java.time.temporal.ChronoUnit;
+import java.util.Date;
 import java.util.Map;
 import java.util.UUID;
 
@@ -126,8 +129,8 @@ public class SsoStateService {
                 .claim("externalId", info.externalId())
                 .claim("unionId", info.unionId())
                 .claim("externalName", info.displayName())
-                .issuedAt(new java.util.Date(now))
-                .expiration(new java.util.Date(now + BIND_TOKEN_TTL_SECONDS * 1000L))
+                .issuedAt(new Date(now))
+                .expiration(new Date(now + BIND_TOKEN_TTL_SECONDS * 1000L))
                 .signWith(getSignKey())
                 .compact();
     }
@@ -166,7 +169,7 @@ public class SsoStateService {
         consumed.setCreatedAt(LocalDateTime.now());
         try {
             stateMapper.insert(consumed);
-        } catch (org.springframework.dao.DuplicateKeyException e) {
+        } catch (DuplicateKeyException e) {
             throw new MateClawException("err.sso.bind_token_used",
                     400, "bind_token 已被使用, 请重新登录");
         }
@@ -213,7 +216,7 @@ public class SsoStateService {
 
     private String hmacSha256Hex(String input) {
         try {
-            javax.crypto.Mac mac = javax.crypto.Mac.getInstance("HmacSHA256");
+            Mac mac = Mac.getInstance("HmacSHA256");
             mac.init(getSignKey());
             byte[] hash = mac.doFinal(input.getBytes(StandardCharsets.UTF_8));
             StringBuilder sb = new StringBuilder();
diff --git a/mateclaw-server/src/main/java/vip/mate/auth/sso/provider/FeishuSsoProvider.java b/mateclaw-server/src/main/java/vip/mate/auth/sso/provider/FeishuSsoProvider.java
index 9f123043..8605e502 100644
--- a/mateclaw-server/src/main/java/vip/mate/auth/sso/provider/FeishuSsoProvider.java
+++ b/mateclaw-server/src/main/java/vip/mate/auth/sso/provider/FeishuSsoProvider.java
@@ -7,6 +7,7 @@ import vip.mate.auth.sso.SsoProperties;
 import vip.mate.exception.MateClawException;
 
 import java.net.URI;
+import java.net.URLEncoder;
 import java.net.http.HttpClient;
 import java.net.http.HttpRequest;
 import java.net.http.HttpResponse;
@@ -221,7 +222,7 @@ public class FeishuSsoProvider implements SsoProvider {
 
     private static String encode(String s) {
         try {
-            return java.net.URLEncoder.encode(s, "UTF-8");
+            return URLEncoder.encode(s, "UTF-8");
         } catch (Exception e) {
             return s;
         }