diff --git a/src/main/java/xuan/service/UserInfoService.java b/src/main/java/xuan/service/UserInfoService.java
index d050087..0b78f50 100644
--- a/src/main/java/xuan/service/UserInfoService.java
+++ b/src/main/java/xuan/service/UserInfoService.java
@@ -70,7 +70,8 @@ public class UserInfoService {
         }
         UserInfo user = userInfoRepository.findByUserId(userId);
         if (user != null) {
-            user.setCoins(user.getCoins() + amount);
+            Integer userCoins = user.getCoins() != null ? user.getCoins() : 0;
+            user.setCoins(userCoins + amount);
             return userInfoRepository.save(user);
         }
         return null;
@@ -82,10 +83,11 @@ public class UserInfoService {
         }
         UserInfo user = userInfoRepository.findByUserId(userId);
         if (user != null) {
-            if (user.getCoins() < amount) {
+            Integer userCoins = user.getCoins() != null ? user.getCoins() : 0;
+            if (userCoins < amount) {
                 throw new IllegalArgumentException("金币不足");
             }
-            user.setCoins(user.getCoins() - amount);
+            user.setCoins(userCoins - amount);
             return userInfoRepository.save(user);
         }
         return null;
@@ -135,10 +137,11 @@ public class UserInfoService {
             if (user.getVipLevel() != null && user.getVipLevel() > 0) {
                 return user;
             }
-            if (user.getCoins() < amount) {
+            Integer userCoins = user.getCoins() != null ? user.getCoins() : 0;
+            if (userCoins < amount) {
                 return null;
             }
-            user.setCoins(user.getCoins() - amount);
+            user.setCoins(userCoins - amount);
             userInfoRepository.save(user);
             
             CoinConsumeRecord record = new CoinConsumeRecord();