I realy have no Idea what this error means... I am trying to use the code to select all the rows under one of the subheaders in a pivot table. I am getting a run time error 100
As JosieP said in the comments, the 1004 error means that there is no such object, that is there is no such pivot field that is called "Row Labels".
I may add an extra answer (as I found nothing on that):
For people working with Data Model Pivot Tables, field names are not obvious ([tablename].[fieldname].[fieldname2]). Hence I suggest using following loop to understand what fields are currently in your pivot table:
Dim pt As PivotTable
Dim pf As PivotField
Set pt = ActiveSheet.PivotTables(ptName)
For Each pf In pt.PivotFields
Debug.Print pf.Name
Next
This way you'll have all the names listed in the immediate view.