Unconstitutional billing process

My experience with Pretor is the worst,I thought escalating the query would get my query resolved,I'm questioning the letigitimacy of their internal processes problem solving and leadership skills of the portfolio manager & the fact that my constitutional rights are undermined as a client and a citizen.I cleared the balance on my levy,the balance was -R114 however it was increased to R2085 due to backdated attorney charges from May which did not appear on any statements previously, all these charges were backdated only appearing on the August 2020 statement .it's a joke the portfolio manager claims that they are doing this to protect clients, on numerous emails I have asked the portfolio manager to quote a law that supports this process he has not been able to do so instead he says the charges on our account may be Increased? According to legislation attorney charges need to be reasonable and constitutional I don't know what gives the portfolio manager the entitlement to think they have the upper hand to Impose/enforce practices that are supported by any law.