First national bank(***** or no respect)

I have posted a complaint on various platforms in order to try and get the correct assistance but i am hopeless. Money was taken out if my account which they hold and which i trusted with and then when i ask where is the money gone or who deducted it then they say they cant do anything the bank was blocked from access to them. How does that work really? I get provided details where as the exact same details is found on google and its invalid contact numbers and emails that dont exist. I want to take this futher since this happened last year September and i am still not receiving feedback regarding this issue. I hope that fnb realizes how much a big of an impact this has on my credit score due to their incompetence.