Incorrect billing and poor service

I have visited the shell garage in laudium on the 05/11, 1stly it is disgusting and poorly kept the quick shop itself is very unhygenic and I am quite certain that it's not up to standard however this is not the basis of my complaint. I was incorrectly billed for goods purchased at the store, instead of R193.5 I was billed R1935.01 only to be told that there is no-one that can help me reverse this as the duty manager was "gone home". I waited over 1h and 30m after several calls to the owner Riaz A****aker who is a very unprofessional and obnoxious person as he said if I make this public it will be because I am trying to "******". He fails to understand that I spent time I will never get back because of his *********** staff and poor management! I was given the cash difference where I have incurred further cost as I had to deposit it back into my acc! The situation was dealt with very poorly and I feel that this particular branch is not up to standard and Shell authorities need to pay them a visit... furthermore I personally will not recommend them to anyone as service is poor and attitude is even worse apart from the unhygenic situation!