Private m_fCmbCell = New DataGridViewComboBoxCell
... 
   заполнение  m_fCmbCell
...

Private Sub DGV_ports_CellBeginEdit(sender As Object, e As DataGridViewCellCancelEventArgs) Handles dgv_ports.CellBeginEdit
      
        If e.ColumnIndex = col_parent.Index Then
          
                m_fCmbCell.Value = dgv_ports.Item(e.ColumnIndex, e.RowIndex).Value
                dgv_ports.Item(e.ColumnIndex, e.RowIndex) = m_fCmbCell
        end if

End Sub

Private Sub DGV_ports_CellEndEdit(sender As Object, e As DataGridViewCellEventArgs) Handles dgv_ports.CellEndEdit
        If e.ColumnIndex = col_parent.Index Then
            
                Dim txtCell = New DataGridViewTextBoxCell

                Dim ss As String = dgv_ports.Item(e.ColumnIndex, e.RowIndex).Value

                txtCell.Value = ss
                dgv_ports.Item(e.ColumnIndex, e.RowIndex) = txtCell
       
        End If
End Sub 

reentrant call to the SetCurrentCellAddressCore