Copy cell value above to cells below if blanks

Hey Everyone,

There is an issue im running into here and I cant figure it out.

I have a program to take account numbers and separate them into single rows, once they populate into the new rows I want to get the blanks to fill with the information from the account in the rows adjacent to them. If I use the last row method the macro returns ref, but if I use a set number of rows this does not occur.

Here is my current code.

Sub TMPfriendly()

    Dim rindex As Long
    Dim saItem() As String
    Dim rng As Range
    Dim LastRow As Long
    Dim ws As Worksheet

    
        Set ws = ActiveSheet
        LastRow = ws.Range("A" & Rows.Count).End(xlUp).Row
        
        For rindex = Cells(Rows.Count, "A").End(xlUp).Row To 1 Step -1
            If InStr(Cells(rindex, "A").Value, "/") > 0 Then
                saItem = Split(Cells(rindex, "A").Value, "/")
                Rows(rindex + 1 & ":" & rindex + UBound(saItem)).Insert
                Cells(rindex, "A").Resize(UBound(saItem) + 1).Value = WorksheetFunction.Transpose(saItem)
            End If
        Next rindex
        
        On Error Resume Next
          
          With Range("A2" & LastRow)
            On Error Resume Next
                Set myRange = .SpecialCells(xlCellTypeBlanks)  'check for blank cells
            On Error GoTo 0
                If Not myRange Is Nothing Then   'if there are blanks then...
               myRange.FormulaR1C1 = "=R[-1]C"   'Formula to return data in cell above
               .Value = .Value    'fix formula vales to fixed constant values
               Else
                End If
         End With
         
         Columns("B:B").Select
         ActiveSheet.Range("$A$1:$R" & LastRow).RemoveDuplicates Columns:=2, Header:=xlYes
         
End Sub

So it breaks column A into individual rows, and then scans for blanks, it should take the information from the cell above, and then copy that into the cell below for columns b-f (G-R) do not need to fill blanks at all they can be left as is.

The problem is the worksheet can change length so I tried to add the last row, now I get REF! instead of the name from the cell above on any instance where there are multiple splits