Not Happy with Nedbank

I have a problem with Nedbank taking too long to get back to me when I send them emails and calling them. I've been having a problem with my credit card being used by someone or some shop is using my credit card to buy stuff, and when I try to get to the bottom of this they tell me to block the card and I get charged for a new card. I want to reverse a transaction that happened to my account and unnecessary charges in June, July of 7.26 every time I buy airtime or data, but I'm not getting help. R375.00 went off my credit card and I know nothing about the transaction, I think I need to make this public on Social media platforms that nedbank doesn't care about their customers.