diff --git a/backend/db.go b/backend/db.go
index 78f41f8..31ba5e3 100644
--- a/backend/db.go
+++ b/backend/db.go
@@ -160,6 +160,22 @@ func (db *Db) DeleteAllowance(userId int, allowanceId int) error {
 	return nil
 }
 
+func (db *Db) UpdateUserAllowance(userId int, allowance *UpdateAllowanceRequest) error {
+	tx, err := db.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.MustRollback()
+
+	err = tx.Query("update users set weight=? where id = ?").
+		Bind(allowance.Weight, userId).
+		Exec()
+	if err != nil {
+		return err
+	}
+	return tx.Commit()
+}
+
 func (db *Db) UpdateAllowance(userId int, allowanceId int, allowance *UpdateAllowanceRequest) error {
 	// Check if the allowance exists for the user
 	count := 0
diff --git a/backend/main.go b/backend/main.go
index 16b20a3..ab99b33 100644
--- a/backend/main.go
+++ b/backend/main.go
@@ -268,7 +268,11 @@ func putUserAllowance(c *gin.Context) {
 		return
 	}
 
-	err = db.UpdateAllowance(userId, allowanceId, &allowanceRequest)
+	if allowanceId == 0 {
+		err = db.UpdateUserAllowance(userId, &allowanceRequest)
+	} else {
+		err = db.UpdateAllowance(userId, allowanceId, &allowanceRequest)
+	}
 	if err != nil {
 		log.Printf("Error updating allowance: %v", err)
 		c.JSON(http.StatusInternalServerError, gin.H{"error": ErrInternalServerError})