Unauthorized debit orders - Upset

I highly upset at the incompetence and attitude of the Gateway old mutual agent. I went there to ask them to help me as I have reported more than 4 time that my accounts are being debited on the wrong day and I am a pensioner and get money on the last day 30th of every month. Today I received a notification that money was deducted again to on the 25th when I asked them to debit my account more than 4 times on the last day and this is such an inconvenience as this is the little money that I have to maintain myself and buy food till the end of the month , where must I get the money now to feed myself and my gran kids .