diff --git a/src/modules/Elsa.Common/Entities/OrderDefinition.cs b/src/modules/Elsa.Common/Entities/OrderDefinition.cs
index 5d1f1ed82..99108ec84 100644
--- a/src/modules/Elsa.Common/Entities/OrderDefinition.cs
+++ b/src/modules/Elsa.Common/Entities/OrderDefinition.cs
@@ -31,5 +31,5 @@ public class OrderDefinition<T, TProp>
     /// <summary>
     /// The key selector to use to order the results.
     /// </summary>
-    public Expression<Func<T, TProp>> KeySelector { get; set; } = default!;
+    public Expression<Func<T, TProp>> KeySelector { get; set; } = null!;
 }
\ No newline at end of file
diff --git a/src/modules/Elsa.Workflows.Management/Models/WorkflowDefinitionSummary.cs b/src/modules/Elsa.Workflows.Management/Models/WorkflowDefinitionSummary.cs
index 718cdd7e7..2f8a71a45 100644
--- a/src/modules/Elsa.Workflows.Management/Models/WorkflowDefinitionSummary.cs
+++ b/src/modules/Elsa.Workflows.Management/Models/WorkflowDefinitionSummary.cs
@@ -51,12 +51,12 @@ public class WorkflowDefinitionSummary
     /// <summary>
     /// The version ID of the workflow definition.
     /// </summary>
-    public string Id { get; set; } = default!;
+    public string Id { get; set; } = null!;
 
     /// <summary>
     /// The ID of the workflow definition.
     /// </summary>
-    public string DefinitionId { get; set; } = default!;
+    public string DefinitionId { get; set; } = null!;
 
     /// <summary>
     /// The name of the workflow definition.
@@ -96,7 +96,7 @@ public class WorkflowDefinitionSummary
     /// <summary>
     /// The materializer name of the workflow definition.
     /// </summary>
-    public string MaterializerName { get; set; } = default!;
+    public string MaterializerName { get; set; } = null!;
 
     /// <summary>
     /// The timestamp when the workflow definition was created.