Im a sassa pensioner and gets my pension every month different dates and the pay my cell c account 5 days prior to debit order day

Im a sassa pensioner and gets my pension every month different dates and the pay my cell c account 5 days prior to debit order day. The debit my acc again and if there is no money they charge me R70 every month for insufficient funds. I was retrenched in 2021. I did complain to their customer care service, nobody seems to help. I cannot afford to loose R70 every month.