It works here in Word 2016?
If you want it to save with the indicated name the first time it is saved then (and you shoukld include some error trapping to ensure the fields are filled, and you won't be able to use Save to save your changes to the code.
Option Explicit
Sub SaveAs_Dialog()
Dim dlgsaveas As Dialog
Set dlgsaveas = Dialogs(wdDialogFileSaveAs)
With dlgsaveas
.Name = ActiveDocument.SelectContentControlsByTag("Name").Item(1).Range.Text & " - " & _
ActiveDocument.SelectContentControlsByTag("Number").Item(1).Range.Text
.Format = wdFormatXMLDocumentMacroEnabled
.Show
End With
End Sub
Sub FileSave()
If Not ActiveDocument.Name = ActiveDocument.SelectContentControlsByTag("Name").Item(1).Range.Text & " - " & _
ActiveDocument.SelectContentControlsByTag("Number").Item(1).Range.Text & ".docm" Then
SaveAs_Dialog
Else
ActiveDocument.Save
End If
End Sub