Object reference not set to an instance object

I am new to UiPath and have been trying out the exercise in Academy: Calculate Client Security Hash.

I am getting error in GetTransactionData: “If More items: Object reference not set to an instance of an object.”
GetTransactionData.xaml (7.9 KB)

I am attaching the workflow files.Calculate Client Security Hash.zip (1.0 MB)
If someone can please check and let me know what I need to fix. Appreciate it. Thank You.

I also have this error, but on a Document Understanding .xaml that I took from Academy: "20.10.2+Branch.master.Sha.cf481ddc1ae94ab83e743f85d96fbfeca8fc705c

Source: Export Extraction Results

Message: Object reference not set to an instance of an object.

Exception Type: System.NullReferenceException

RemoteException wrapping System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.IntelligentOCR.Activities.DataExtraction.ExportExtractionResults.Execute(CodeActivityContext context)
at System.Activities.CodeActivity.InternalExecute(ActivityInstance instance, ActivityExecutor executor, BookmarkManager bookmarkManager)
at System.Activities.ActivityInstance.Execute(ActivityExecutor executor, BookmarkManager bookmarkManager)
at System.Activities.Runtime.ActivityExecutor.ExecuteActivityWorkItem.ExecuteBody(ActivityExecutor executor, BookmarkManager bookmarkManager, Location resultLocation)"
The invoice extraction works fine with the examples provided by the Academy, but not with any other editable .pdf invoices