Never ceases to disappoint

This bank never ceases to disappoint. I have a medical aid debit order that went off, there was not enough money in my account. I have cancelled the membership, unfortunately it was too late as the debit was already sent to my bank. What I do not understand is why FNB has honoured this debit on my behlaf...I am sitting on a huge negative and I have now been charged R450 for insufficient funds...because you chose to honour a debit seeing that I did not have enough money to cover that debit. The money that you took was suppose to pay the uber rides that are now on insufficient charges...those insufficient funds are for UBER...not even more that R50 for the 3 trips, but you have charged me R450. Get real!! How can you charge me R150 for R26 insufficient funds???