FNB Charges R220 for R36 Unpaid!

On 30 March 2018 I went through two toll gates. It was thus R18 x 2, R36 in total. At that time, I had sufficient funds in my account. On 18 April 2018 only, FNB tried to deduct the money but my account was unfortunately in the minus. They charged me R220 in total for the above mentioned, R110 for each R18! This is absurd! It is not my fault that the money was not deducted in time! I have e-mailed ********** but have not received a resolution. Only a reference number. This is such a clever way to not deduct the money in time and then charge you such an astronomous amount! I am going to close my account if this is not reversed very soon and move to another bank, as easy as that.