diff --git a/barker/barker/routers/reports/product_sale_report.py b/barker/barker/routers/reports/product_sale_report.py
index facc981..e183274 100644
--- a/barker/barker/routers/reports/product_sale_report.py
+++ b/barker/barker/routers/reports/product_sale_report.py
@@ -89,7 +89,9 @@ def product_sale_report(s: date, f: date, db: Session):
         type_ = to_camel(VoucherType(type_).name)
         old = [i for i in info if i["id"] == id_ and i["isHappyHour"] == hh]
         if len(old):
-            old[0][type_] = quantity
+            if type_ not in old[0]:
+                old[0][type_] = 0
+            old[0][type_] += quantity
         else:
             info.append(
                 {