diff --git a/src/JsonApiDotNetCore/Controllers/BaseJsonApiController.cs b/src/JsonApiDotNetCore/Controllers/BaseJsonApiController.cs
index f4041e97d6..fd6ec8947a 100644
--- a/src/JsonApiDotNetCore/Controllers/BaseJsonApiController.cs
+++ b/src/JsonApiDotNetCore/Controllers/BaseJsonApiController.cs
@@ -146,13 +146,15 @@ public virtual async Task<IActionResult> GetRelationshipAsync(TId id, string rel
 
         public virtual async Task<IActionResult> PostAsync([FromBody] T entity)
         {
-            if (_create == null) throw Exceptions.UnSupportedRequestMethod;
+            if (_create == null)
+                throw Exceptions.UnSupportedRequestMethod;
 
             if (entity == null)
                 return UnprocessableEntity();
 
             if (!_jsonApiContext.Options.AllowClientGeneratedIds && !string.IsNullOrEmpty(entity.StringId))
                 return Forbidden();
+
             if (_jsonApiContext.Options.ValidateModelState && !ModelState.IsValid)
                 return BadRequest(ModelState.ConvertToErrorCollection());
 
diff --git a/src/JsonApiDotNetCore/Extensions/ModelStateExtensions.cs b/src/JsonApiDotNetCore/Extensions/ModelStateExtensions.cs
index 8eb0fc95f7..d67f7e66c4 100644
--- a/src/JsonApiDotNetCore/Extensions/ModelStateExtensions.cs
+++ b/src/JsonApiDotNetCore/Extensions/ModelStateExtensions.cs
@@ -8,17 +8,22 @@ public static class ModelStateExtensions
     {
         public static ErrorCollection ConvertToErrorCollection(this ModelStateDictionary modelState)
         {
-            ErrorCollection errors = new ErrorCollection();
+            ErrorCollection collection = new ErrorCollection();
             foreach (var entry in modelState)
             {
-                if (!entry.Value.Errors.Any())
+                if (entry.Value.Errors.Any() == false)
                     continue;
+
                 foreach (var modelError in entry.Value.Errors)
                 {
-                    errors.Errors.Add(new Error(400, entry.Key, modelError.ErrorMessage, modelError.Exception != null ? ErrorMeta.FromException(modelError.Exception) : null));
+                    if (modelError.Exception is JsonApiException jex)
+                        collection.Errors.AddRange(jex.GetError().Errors);
+                    else
+                        collection.Errors.Add(new Error(400, entry.Key, modelError.ErrorMessage, modelError.Exception != null ? ErrorMeta.FromException(modelError.Exception) : null));
                 }
             }
-            return errors;
+
+            return collection;
         }
     }
 }
diff --git a/src/JsonApiDotNetCore/Formatters/JsonApiReader.cs b/src/JsonApiDotNetCore/Formatters/JsonApiReader.cs
index 204f3e0491..e10a3f31c2 100644
--- a/src/JsonApiDotNetCore/Formatters/JsonApiReader.cs
+++ b/src/JsonApiDotNetCore/Formatters/JsonApiReader.cs
@@ -52,11 +52,9 @@ public Task<InputFormatterResult> ReadAsync(InputFormatterContext context)
                 context.ModelState.AddModelError(context.ModelName, ex, context.Metadata);
                 return InputFormatterResult.FailureAsync();
             }
-            catch (JsonApiException jex)
+            catch (JsonApiException)
             {
-                _logger?.LogError(new EventId(), jex, "An error occurred while de-serializing the payload");
-                context.ModelState.AddModelError(context.ModelName, jex, context.Metadata);
-                return InputFormatterResult.FailureAsync();
+                throw;
             }
         }
 
diff --git a/src/JsonApiDotNetCore/JsonApiDotNetCore.csproj b/src/JsonApiDotNetCore/JsonApiDotNetCore.csproj
index cc337c28dc..a212eecd70 100755
--- a/src/JsonApiDotNetCore/JsonApiDotNetCore.csproj
+++ b/src/JsonApiDotNetCore/JsonApiDotNetCore.csproj
@@ -1,6 +1,6 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <VersionPrefix>2.3.3</VersionPrefix>
+    <VersionPrefix>2.3.4</VersionPrefix>
     <TargetFrameworks>$(NetStandardVersion)</TargetFrameworks>
     <AssemblyName>JsonApiDotNetCore</AssemblyName>
     <PackageId>JsonApiDotNetCore</PackageId>
diff --git a/src/JsonApiDotNetCore/Serialization/JsonApiDeSerializer.cs b/src/JsonApiDotNetCore/Serialization/JsonApiDeSerializer.cs
index a1e3c76214..285923995d 100644
--- a/src/JsonApiDotNetCore/Serialization/JsonApiDeSerializer.cs
+++ b/src/JsonApiDotNetCore/Serialization/JsonApiDeSerializer.cs
@@ -57,6 +57,10 @@ public object Deserialize(string requestBody)
                 var entity = DocumentToObject(document.Data, document.Included);
                 return entity;
             }
+            catch (JsonApiException)
+            {
+                throw;
+            }
             catch (Exception e)
             {
                 throw new JsonApiException(400, "Failed to deserialize request body", e);
@@ -109,10 +113,15 @@ public List<TEntity> DeserializeList<TEntity>(string requestBody)
 
         public object DocumentToObject(DocumentData data, List<DocumentData> included = null)
         {
-            if (data == null) throw new JsonApiException(422, "Failed to deserialize document as json:api.");
+            if (data == null)
+                throw new JsonApiException(422, "Failed to deserialize document as json:api.");
 
             var contextEntity = _jsonApiContext.ContextGraph.GetContextEntity(data.Type?.ToString());
-            _jsonApiContext.RequestEntity = contextEntity;
+            _jsonApiContext.RequestEntity = contextEntity ?? throw new JsonApiException(400,
+                    message: $"This API does not contain a json:api resource named '{data.Type}'.",
+                    detail: "This resource is not registered on the ContextGraph. "
+                            + "If you are using Entity Framework, make sure the DbSet matches the expected resource name. "
+                            + "If you have manually registered the resource, check that the call to AddResource correctly sets the public name."); ;
 
             var entity = Activator.CreateInstance(contextEntity.EntityType);
 
diff --git a/test/UnitTests/Models/IdentifiableTests.cs b/test/UnitTests/Models/IdentifiableTests.cs
new file mode 100644
index 0000000000..778b1b485f
--- /dev/null
+++ b/test/UnitTests/Models/IdentifiableTests.cs
@@ -0,0 +1,26 @@
+using JsonApiDotNetCore.Models;
+using Xunit;
+
+namespace UnitTests.Models
+{
+    public class IdentifiableTests
+    {
+        [Fact]
+        public void Can_Set_StringId_To_Value_Type()
+        {
+            var resource = new IntId();
+            resource.StringId = "1";
+            Assert.Equal(1, resource.Id);
+        }
+
+        [Fact]
+        public void Setting_StringId_To_Null_Sets_Id_As_Default()
+        {
+            var resource = new IntId();
+            resource.StringId = null;
+            Assert.Equal(0, resource.Id);
+        }
+
+        private class IntId : Identifiable { }
+    }
+}