Excessive cost items on account

I bought some groceries on 30 April 2020.I forgot a small item and present my card again. I tried twice before realising that the reason for the card being declined was the R8. 35 payment cost that I forgot. This morning I was quite surprised to notice two cost items of R8. 60 per item on my account. Total being R17. 20. I posted my enquiry on your face book page with refs. BDS ABSA 0*** INS FUNDS and BDS ABSA 0*** INS FUNDS. They subsequently informed me it was for declined transactions. I did not want to pursue this matter further on a social platforn, but want to state I find these costs excessive. I made an honest mistake and want to ask you if you can please reverse these costs. It is the first time, as far as I can remember, that something like this happened to me with my account. I also queried it on your money app. Regards Michel de Beer.