Unreasonable charges

For the past three or four months Nedbank has been charging me R7.26 every time I bought airtime or data using my credit card of which it's not supposed to be like that, and I have been calling and telling them and reporting this but the reply I always get is that we are still investigating and will get back to you. I am done with this bank I will take this to Twitter and Facebook so that others will see that you do not care about your customers. Nedbank and Capitec they are the same whatsapp group of irresponsible banks that don't care for their customers.