diff --git a/npm/ng-packs/packages/core/src/lib/states/config.state.ts b/npm/ng-packs/packages/core/src/lib/states/config.state.ts
index 2232fd0419..debbc9b8a0 100644
--- a/npm/ng-packs/packages/core/src/lib/states/config.state.ts
+++ b/npm/ng-packs/packages/core/src/lib/states/config.state.ts
@@ -249,7 +249,7 @@ export class ConfigState {
       if (index < 0) return;
 
       const parent = flattedRoutes[index];
-      if (parent.url.replace('/', '')) {
+      if ((parent.url || '').replace('/', '')) {
         route.url = `${parent.url}/${route.path}`;
       } else {
         route.url = `/${route.path}`;