diff --git a/api/spec/packages/aip-client-javascript/tests/nesting.spec.ts b/api/spec/packages/aip-client-javascript/tests/nesting.spec.ts
index a52423845a..1e3e85d9de 100644
--- a/api/spec/packages/aip-client-javascript/tests/nesting.spec.ts
+++ b/api/spec/packages/aip-client-javascript/tests/nesting.spec.ts
@@ -28,7 +28,7 @@ describe('nested sub-clients', () => {
       validate: true,
     })
 
-    const result = await sdk.customers.charges.invoice({
+    const result = await sdk.internal.customers.charges.invoice({
       customerId: '01ARZ3NDEKTSV4RRFFQ69G5FAV',
       body: {},
     })
diff --git a/api/spec/packages/typespec-typescript/templates/tests/nesting.spec.ts b/api/spec/packages/typespec-typescript/templates/tests/nesting.spec.ts
index fe5a815f5c..3c3b1c8f03 100644
--- a/api/spec/packages/typespec-typescript/templates/tests/nesting.spec.ts
+++ b/api/spec/packages/typespec-typescript/templates/tests/nesting.spec.ts
@@ -26,7 +26,7 @@ describe('nested sub-clients', () => {
       validate: true,
     })
 
-    const result = await sdk.customers.charges.invoice({
+    const result = await sdk.internal.customers.charges.invoice({
       customerId: '01ARZ3NDEKTSV4RRFFQ69G5FAV',
       body: {},
     })
diff --git a/api/v3/handlers/billinginvoices/invoice_charges.go b/api/v3/handlers/billinginvoices/invoice_charges.go
index 1cd7bf4429..ff415d921a 100644
--- a/api/v3/handlers/billinginvoices/invoice_charges.go
+++ b/api/v3/handlers/billinginvoices/invoice_charges.go
@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/samber/lo"
+
 	api "github.com/openmeterio/openmeter/api/v3"
 	"github.com/openmeterio/openmeter/api/v3/apierrors"
 	"github.com/openmeterio/openmeter/api/v3/request"
@@ -13,7 +15,6 @@ import (
 	"github.com/openmeterio/openmeter/pkg/framework/commonhttp"
 	"github.com/openmeterio/openmeter/pkg/framework/transport/httptransport"
 	"github.com/openmeterio/openmeter/pkg/slicesx"
-	"github.com/samber/lo"
 )
 
 type (