alert api error message

@@ -36,7 +36,7 @@ const acquireAsync = (cid, uid) => {
             default:
                 return {
                     code: 500,
-                    message: '领券失败！'
+                    message: result.message
                 };
         }
     });

@@ -158,13 +158,16 @@ bindEvent.add(function() {
             couponId: cid
         }).then(function(result) {
             var defer = $.Deferred(); //eslint-disable-line
-
+            var couponAlert;
+            
             if (result.code === 200) {
                 defer.resolve();
             } else if (result.code === 400) {
                 defer.reject({refer: window.signinUrl()});
             } else {
                 defer.reject();
+                couponAlert = new Alert(result.message);
+                couponAlert.show();
             }
 
             return defer.promise();