限购判断小于0

app/Api/Controllers/DrugController.php

@@ -171,7 +171,7 @@ public function drugLimit(Request $request)
                 $mahuangsu_num += $drug['num'];
                 $drug['mahuangsu_status'] = 1; // 1：是麻黄素药品
                 $canBuyMahuangCount = 4 - $buyed_mahuang_counts - $mahuangsu_num; // 麻黄素药品剩余可购买数量，最多可以购买4个
-                if ($canBuyMahuangCount <= 0) {
+                if ($canBuyMahuangCount < 0) {
                     $errMsg = '药品['.$drugModel->name.']剩余购买数量不足~';
 
                     return $this->failed($errMsg, ['add_status' => false]);