diff --git a/billing/filters.py b/billing/filters.py
index c316e4f..97af140 100644
--- a/billing/filters.py
+++ b/billing/filters.py
@@ -1,5 +1,6 @@
 import django_filters
 from .models import Payment, Topup
+from django.db.models import Q
 
 
 class PaymentFilter(django_filters.FilterSet):
@@ -21,11 +22,25 @@ class PaymentFilter(django_filters.FilterSet):
 class TopupFilter(django_filters.FilterSet):
     amount = django_filters.RangeFilter(field_name="amount")
     paid = django_filters.BooleanFilter(field_name="paid")
-    user = django_filters.CharFilter(
-        field_name="user__username", lookup_expr="icontains"
-    )
-    created_at = django_filters.DateFromToRangeFilter()
+    user = django_filters.CharFilter(method="filter_user_search")
+    created_at = django_filters.DateFromToRangeFilter(field_name="created_at")
+
+    def filter_user_search(self, queryset, name, value):
+        """
+        Search across multiple user fields: first_name, last_name, id_card, mobile
+        """
+        return queryset.filter(
+            Q(user__first_name__icontains=value)
+            | Q(user__last_name__icontains=value)
+            | Q(user__id_card__icontains=value)
+            | Q(user__mobile__icontains=value)
+        )
 
     class Meta:
         model = Topup  # Assuming Topup is a subclass of Payment
-        fields = "__all__"
+        fields = [
+            "amount",
+            "paid",
+            "user",
+            "created_at",
+        ]