bugfixed

pages/scan/scan.js

@@ -129,6 +129,7 @@ Page({
         let req = {}
         req.discCouponMsg = "超额优惠券"
         req.discCouponState = 4;
+        req.discCouponPrice = this.data.totalDisc
         this.useCouponCallback(ACTION_USE_COUPON, req)
         return
       }