update

src/main/java/com/gogirl/domain/order/serve/OrderServe.java

@@ -266,5 +266,7 @@ public class OrderServe implements Serializable {
         this.achievement = this.achievement.subtract(timesCardUsedRecord.getDiscountAmount()).add(timesCardUsedRecord.getPayAmount());
     }
 
-
+    public void setAchievement(BigDecimal achievement) {
+        this.achievement = achievement.max(BigDecimal.ZERO);
+    }
 }
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