diff --git a/framework/src/Volo.Abp.AspNetCore.Components.MauiBlazor/Volo/Abp/AspNetCore/Components/MauiBlazor/ApplicationConfigurationCache.cs b/framework/src/Volo.Abp.AspNetCore.Components.MauiBlazor/Volo/Abp/AspNetCore/Components/MauiBlazor/ApplicationConfigurationCache.cs
index f4857165f7..b5ca46e7d8 100644
--- a/framework/src/Volo.Abp.AspNetCore.Components.MauiBlazor/Volo/Abp/AspNetCore/Components/MauiBlazor/ApplicationConfigurationCache.cs
+++ b/framework/src/Volo.Abp.AspNetCore.Components.MauiBlazor/Volo/Abp/AspNetCore/Components/MauiBlazor/ApplicationConfigurationCache.cs
@@ -9,7 +9,7 @@ public class ApplicationConfigurationCache : ISingletonDependency
 {
     protected ApplicationConfigurationDto? Configuration { get; set; }
 
-    public event Action ApplicationConfigurationChanged = default!;
+    public event Action? ApplicationConfigurationChanged;
 
     public virtual ApplicationConfigurationDto? Get()
     {