diff --git a/billing/serializers.py b/billing/serializers.py
index a21616f..72e71e9 100644
--- a/billing/serializers.py
+++ b/billing/serializers.py
@@ -44,6 +44,7 @@ class TopupSerializer(serializers.ModelSerializer):
             "amount",
             "user",
             "paid",
+            "paid_at",
             "status",
             "mib_reference",
             "is_expired",