Object reference not set to an instance of an object.
at Amazon.DynamoDBv2.Model.Internal.MarshallTransformations.AttributeValueMarshaller.Marshall(AttributeValue requestObject, JsonMarshallerContext context) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcServicesDynamoDBv2GeneratedModelInternalMarshallTransformationsAttributeValueMarshaller.cs:line 48
   at Amazon.DynamoDBv2.Model.Internal.MarshallTransformations.UpdateItemRequestMarshaller.Marshall(UpdateItemRequest publicRequest) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcServicesDynamoDBv2GeneratedModelInternalMarshallTransformationsUpdateItemRequestMarshaller.cs:line 165
   at Amazon.Runtime.Internal.Marshaller.PreInvoke(IExecutionContext executionContext) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcCoreAmazon.RuntimePipelineHandlersMarshaller.cs:line 79
   at Amazon.Runtime.Internal.Marshaller.InvokeAsync[T](IExecutionContext executionContext) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcCoreAmazon.RuntimePipelineHandlersMarshaller.cs:line 51
   at Amazon.Runtime.Internal.CallbackHandler.InvokeAsync[T](IExecutionContext executionContext) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcCoreAmazon.RuntimePipelineHandlersCallbackHandler.cs:line 60
   at Amazon.Runtime.Internal.ErrorCallbackHandler.InvokeAsync[T](IExecutionContext executionContext)
   at Amazon.Runtime.Internal.MetricsHandler.InvokeAsync[T](IExecutionContext executionContext)
   at Amazon.DynamoDBv2.DocumentModel.Table.UpdateHelperAsync(Document doc, Key key, UpdateItemOperationConfig config, CancellationToken cancellationToken) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcServicesDynamoDBv2CustomDocumentModelTable.cs:line 871
   at Amazon.DynamoDBv2.DataModel.DynamoDBContext.SaveHelperAsync[T](T value, DynamoDBOperationConfig operationConfig, CancellationToken cancellationToken) in D:JenkinsWorkspacestrebuchet-stage-releaseAWSDotNetPublicsdksrcServicesDynamoDBv2CustomDataModelContext.cs:line 285