policy lapsed due to incorrect debit date

I have been paying the funeral policy since 2006. My debit date was the 26th of the month. Unfortunately due to financial difficulties my September premium was unpaid. I was expecting to pay double on next debit date 25th October. However hollard insurance decided to debit my acc on 26th. Unfortunately there was insufficient amount on my acc because I made sure there was finds on 25th. My policy has now lapsed & I have to wait 6 months waiting period. I feel I was unfairly treated & I'm lodging a complaint with the Ombuds