insertbefore in all cells and columns

[karkey]

Sub InsertTableTags()

Dim tbl As Table
Dim rng As Range
Dim row As row

' Loop through all tables in the document
For Each tbl In ActiveDocument.Tables
    Set rng = tbl.Range

    ' Check if all columns are merged
    If tbl.Rows(2).Cells.Count > 1 Then
        ' Insert <TC> in first row
        rng.Cells(1).Range.InsertBefore Text:="<TC>"
        
    End If

    ' Loop through rows in the table
    For Each row In tbl.Rows
        Set rng = row.Range

        ' Check if current row is the second row
        If row.Index = 2 Then
            ' Check if all columns are merged
            If tbl.Rows(2).Cells.Count > 1 Then
                ' Insert <TCH> in second row
                rng.Cells(1).Range.InsertBefore Text:="<TCH>"
            End If
        ' Check if current row is not the first or last row
        ElseIf row.Index > 2 And row.Index < tbl.Rows.Count Then
            ' Insert <TT> in all cells
            rng.Cells(1).Range.InsertBefore Text:="<TT>"
        ' Check if current row is the last row
        ElseIf row.Index = tbl.Rows.Count Then
            ' Check if all columns are merged
            If tbl.Rows(tbl.Rows.Count).Cells.Count > 1 Then
                ' Insert <TTL> in last row
                rng.Cells(1).Range.InsertBefore Text:="<TTL>"
            End If

            ' Check if "Source", "Notes", or "Note" is found in the last row
            If InStr(rng.Text, "Source") > 0 Or InStr(rng.Text, "Notes") > 0 Or InStr(rng.Text, "Note") > 0 Then
                ' Insert <TTS> in all cells of the last row
                rng.Cells(1).Range.InsertBefore Text:="<TTS>"
            End If
        End If
    Next row
Next tbl

End Sub

while run the above code it insertBefore only in 1st column need to insert in all columns