diff --git a/apps/inm/serializers.py b/apps/inm/serializers.py
index 1ea7604e..760fe0b0 100644
--- a/apps/inm/serializers.py
+++ b/apps/inm/serializers.py
@@ -72,7 +72,7 @@ class MIOListSerializer(CustomModelSerializer):
         source='customer.name', read_only=True)
     order_number = serializers.CharField(source='order.number', read_only=True)
     pu_order_number = serializers.CharField(
-        source='pu_order.name', read_only=True)
+        source='pu_order.number', read_only=True)
 
     class Meta:
         model = MIO