Why Gridview Count Zero

private void DeleteLateAttendance()
        {
            LateAttendanceRepository LateRepository = new LateAttendanceRepository();
            LateAttendanceApprovalDto LateApprovalDto = new LateAttendanceApprovalDto();
            int count = grdLateAttendance.Rows.Count;
            foreach (GridViewRow gvRow in grdLateAttendance.Rows)
            {
                CheckBox chk = gvRow.FindControl("chkDelete") as CheckBox;
                if (chk != null && chk.Checked)
                {
                    LateApprovalDto.LateAttendanceApprovalID= gvRow.Cells[1].Text.Trim();
                    LateRepository.DeleteLateAttendance(LateApprovalDto.LateAttendanceApprovalID);
                }

            }
        }