diff --git a/modules/openiddict/src/Volo.Abp.OpenIddict.AspNetCore/Microsoft/Extensions/DependencyInjection/OpenIddictServerBuilderExtensions.cs b/modules/openiddict/src/Volo.Abp.OpenIddict.AspNetCore/Microsoft/Extensions/DependencyInjection/OpenIddictServerBuilderExtensions.cs
index e5f2d7222a..7ba0fc9340 100644
--- a/modules/openiddict/src/Volo.Abp.OpenIddict.AspNetCore/Microsoft/Extensions/DependencyInjection/OpenIddictServerBuilderExtensions.cs
+++ b/modules/openiddict/src/Volo.Abp.OpenIddict.AspNetCore/Microsoft/Extensions/DependencyInjection/OpenIddictServerBuilderExtensions.cs
@@ -5,7 +5,7 @@ namespace Microsoft.Extensions.DependencyInjection;
 
 public static class OpenIddictServerBuilderExtensions
 {
-    public static OpenIddictServerBuilder AddProductionEncryptionAndSigningCertificate(this OpenIddictServerBuilder builder, string fileName, string passPhrase, X509KeyStorageFlags? flag)
+    public static OpenIddictServerBuilder AddProductionEncryptionAndSigningCertificate(this OpenIddictServerBuilder builder, string fileName, string passPhrase, X509KeyStorageFlags? flag = null)
     {
         if (!File.Exists(fileName))
         {