This bank is finding different ways every month to get money from me.

I do not understand why is FNB charging me R193 #FNB OM PMT NAEDO*** I called FNB call center before the 25th to change personal debit order to the 28th and I was told they system does not allow them to and asked the consultant if I was not going to be charged and she said NO but to my surprise now FNB is charging me. This bank is finding different ways every month to get money from me.