diff --git a/controller/user.go b/controller/user.go
index 1e227bbbd..db078071e 100644
--- a/controller/user.go
+++ b/controller/user.go
@@ -2,6 +2,7 @@ package controller
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -213,10 +214,7 @@ func Register(c *gin.Context) {
 			token.Group = "auto"
 		}
 		if err := token.Insert(); err != nil {
-			c.JSON(http.StatusOK, gin.H{
-				"success": false,
-				"message": "创建默认令牌失败",
-			})
+			common.ApiErrorI18n(c, i18n.MsgCreateDefaultTokenErr)
 			return
 		}
 	}
@@ -294,20 +292,14 @@ func GenerateAccessToken(c *gin.Context) {
 	randI := common.GetRandomInt(4)
 	key, err := common.GenerateRandomKey(29 + randI)
 	if err != nil {
-		c.JSON(http.StatusOK, gin.H{
-			"success": false,
-			"message": "生成失败",
-		})
+		common.ApiErrorI18n(c, i18n.MsgGenerateFailed)
 		common.SysLog("failed to generate key: " + err.Error())
 		return
 	}
 	user.SetAccessToken(key)
 
 	if model.DB.Where("access_token = ?", user.AccessToken).First(user).RowsAffected != 0 {
-		c.JSON(http.StatusOK, gin.H{
-			"success": false,
-			"message": "请重试，系统生成的 UUID 竟然重复了！",
-		})
+		common.ApiErrorI18n(c, i18n.MsgUuidDuplicate)
 		return
 	}
 
@@ -658,18 +650,12 @@ func UpdateSelf(c *gin.Context) {
 	var user model.User
 	requestDataBytes, err := json.Marshal(requestData)
 	if err != nil {
-		c.JSON(http.StatusOK, gin.H{
-			"success": false,
-			"message": "无效的参数",
-		})
+		common.ApiErrorI18n(c, i18n.MsgInvalidParams)
 		return
 	}
 	err = json.Unmarshal(requestDataBytes, &user)
 	if err != nil {
-		c.JSON(http.StatusOK, gin.H{
-			"success": false,
-			"message": "无效的参数",
-		})
+		common.ApiErrorI18n(c, i18n.MsgInvalidParams)
 		return
 	}
 
@@ -677,10 +663,7 @@ func UpdateSelf(c *gin.Context) {
 		user.Password = "$I_LOVE_U" // make Validator happy :)
 	}
 	if err := common.Validate.Struct(&user); err != nil {
-		c.JSON(http.StatusOK, gin.H{
-			"success": false,
-			"message": "输入不合法 " + err.Error(),
-		})
+		common.ApiErrorI18n(c, i18n.MsgInvalidInput)
 		return
 	}
 
@@ -996,6 +979,10 @@ func TopUp(c *gin.Context) {
 	}
 	quota, err := model.Redeem(req.Key, id)
 	if err != nil {
+		if errors.Is(err, model.ErrRedeemFailed) {
+			common.ApiErrorI18n(c, i18n.MsgRedeemFailed)
+			return
+		}
 		common.ApiError(c, err)
 		return
 	}
@@ -1149,10 +1136,7 @@ func UpdateUserSetting(c *gin.Context) {
 	// 更新用户设置
 	user.SetSetting(settings)
 	if err := user.Update(false); err != nil {
-		c.JSON(http.StatusOK, gin.H{
-			"success": false,
-			"message": "更新设置失败: " + err.Error(),
-		})
+		common.ApiErrorI18n(c, i18n.MsgUpdateFailed)
 		return
 	}
 
diff --git a/i18n/keys.go b/i18n/keys.go
index 0e63efe8d..5de0d43b2 100644
--- a/i18n/keys.go
+++ b/i18n/keys.go
@@ -268,3 +268,11 @@ const (
 	MsgOAuthGetUserErr  = "oauth.get_user_error"
 	MsgOAuthAccountUsed = "oauth.account_used"
 )
+
+// Model layer error messages (for translation in controller)
+const (
+	MsgRedeemFailed          = "redeem.failed"
+	MsgCreateDefaultTokenErr = "user.create_default_token_error"
+	MsgUuidDuplicate         = "common.uuid_duplicate"
+	MsgInvalidInput          = "common.invalid_input"
+)
diff --git a/i18n/locales/en.yaml b/i18n/locales/en.yaml
index 0705488e0..994ff7837 100644
--- a/i18n/locales/en.yaml
+++ b/i18n/locales/en.yaml
@@ -223,3 +223,9 @@ ability.repair_running: "A repair task is already running, please try again late
 oauth.invalid_code: "Invalid authorization code"
 oauth.get_user_error: "Failed to get user information"
 oauth.account_used: "This account has been bound to another user"
+
+# Model layer error messages
+redeem.failed: "Redemption failed, please try again later"
+user.create_default_token_error: "Failed to create default token"
+common.uuid_duplicate: "Please retry, the system generated a duplicate UUID!"
+common.invalid_input: "Invalid input"
diff --git a/i18n/locales/zh.yaml b/i18n/locales/zh.yaml
index b953c00a1..58576ac7c 100644
--- a/i18n/locales/zh.yaml
+++ b/i18n/locales/zh.yaml
@@ -224,3 +224,9 @@ ability.repair_running: "已经有一个修复任务在运行中，请稍后再
 oauth.invalid_code: "无效的授权码"
 oauth.get_user_error: "获取用户信息失败"
 oauth.account_used: "该账户已被其他用户绑定"
+
+# Model layer error messages
+redeem.failed: "兑换失败，请稍后重试"
+user.create_default_token_error: "创建默认令牌失败"
+common.uuid_duplicate: "请重试，系统生成的 UUID 竟然重复了！"
+common.invalid_input: "输入不合法"
diff --git a/model/redemption.go b/model/redemption.go
index 237561bec..378976a36 100644
--- a/model/redemption.go
+++ b/model/redemption.go
@@ -11,6 +11,9 @@ import (
 	"gorm.io/gorm"
 )
 
+// ErrRedeemFailed is returned when redemption fails due to database error
+var ErrRedeemFailed = errors.New("redeem.failed")
+
 type Redemption struct {
 	Id           int            `json:"id"`
 	UserId       int            `json:"user_id"`
@@ -149,7 +152,7 @@ func Redeem(key string, userId int) (quota int, err error) {
 	})
 	if err != nil {
 		common.SysError("redemption failed: " + err.Error())
-		return 0, errors.New("兑换失败，请稍后重试")
+		return 0, ErrRedeemFailed
 	}
 	RecordLog(userId, LogTypeTopup, fmt.Sprintf("通过兑换码充值 %s，兑换码ID %d", logger.LogQuota(redemption.Quota), redemption.Id))
 	return redemption.Quota, nil