FNB Car insurance - I've had the worst Service since the beginning

I took out cover with FNB car Insurance on 31st August 2018 with Zakhele. They didn't put the debit order through on the 7th of September because they said their debit order run for the 7th was already done, that they will do it the following month on 7 October 2018. They did run it on 7 October and I just found out today that they only double debited, but did not debit the pro-rata for 31 August, I provided for my debit order this month, and this morning I get an SMS from them telling me that my policy has lapsed, because the debit order was not provided for. Apparently their debit order this month include the pro-rata of August.