diff --git a/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationExtensions.cs b/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationExtensions.cs
index 5867f694..04251101 100644
--- a/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationExtensions.cs
+++ b/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationExtensions.cs
@@ -89,12 +89,18 @@ namespace Dapr.Extensions.Configuration
             ArgumentVerifier.ThrowIfNullOrEmpty(store, nameof(store));
             ArgumentVerifier.ThrowIfNull(client, nameof(client));
 
-            configurationBuilder.Add(new DaprSecretStoreConfigurationSource()
+            var source = new DaprSecretStoreConfigurationSource
             {
                 Store = store,
-                KeyDelimiters = keyDelimiters?.ToList(),
                 Client = client
-            });
+            };
+
+            if (keyDelimiters != null)
+            {
+                source.KeyDelimiters = keyDelimiters.ToList();
+            }
+
+            configurationBuilder.Add(source);
 
             return configurationBuilder;
         }
diff --git a/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationSource.cs b/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationSource.cs
index 72e3c2cd..be2c4748 100644
--- a/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationSource.cs
+++ b/src/Dapr.Extensions.Configuration/DaprSecretStoreConfigurationSource.cs
@@ -18,7 +18,7 @@ namespace Dapr.Extensions.Configuration.DaprSecretStore
         /// <summary>
         /// Gets or sets the store name.
         /// </summary>
-        public string? Store { get; set; }
+        public string Store { get; set; } = string.Empty;
 
         /// <summary>
         /// Gets or sets a value indicating whether any key delimiters should be replaced with the delimiter ":".
@@ -29,7 +29,7 @@ namespace Dapr.Extensions.Configuration.DaprSecretStore
         /// <summary>
         /// Gets or sets the custom key delimiters. Contains the '__' delimiter by default.
         /// </summary>
-        public IList<string>? KeyDelimiters { get; set; } = new List<string> { "__" };
+        public IList<string> KeyDelimiters { get; set; } = new List<string> { "__" };
 
         /// <summary>
         /// Gets or sets the secret descriptors.
@@ -44,7 +44,7 @@ namespace Dapr.Extensions.Configuration.DaprSecretStore
         /// <summary>
         /// Gets or sets the http client.
         /// </summary>
-        public DaprClient? Client { get; set; }
+        public DaprClient Client { get; set; } = default!;
 
         /// <inheritdoc />
         public IConfigurationProvider Build(IConfigurationBuilder builder)
@@ -56,11 +56,11 @@ namespace Dapr.Extensions.Configuration.DaprSecretStore
                     throw new ArgumentException($"{nameof(Metadata)} must be null when {nameof(SecretDescriptors)} is set", nameof(Metadata));
                 }
 
-                return new DaprSecretStoreConfigurationProvider(Store!, NormalizeKey, KeyDelimiters, SecretDescriptors, Client!);
+                return new DaprSecretStoreConfigurationProvider(Store, NormalizeKey, KeyDelimiters, SecretDescriptors, Client);
             }
             else
             {
-                return new DaprSecretStoreConfigurationProvider(Store!, NormalizeKey, KeyDelimiters, Metadata, Client!);
+                return new DaprSecretStoreConfigurationProvider(Store, NormalizeKey, KeyDelimiters, Metadata, Client);
             }
         }
     }