Pay it even if you did not ask for it BP on Grayst

HI my name is Kagiso Hlalethwa and on Saturday the 29th of August in the morning i was on my way to a funeral i got to the BP Garage on Grayston drive, I asked the attendant to put in R180 worth of petrol instead he put in full tank, i talk to him and he asked me very nicely not to call the manager because he might loose his job , i ask him what is the solution he says i must pay it up, i then call the manager which comes back to me and says that he is taking his employees side of the story so i must pay it, he then calls the police on a theft charge , they keept on saying to me that the petrol is already in my car and that im going to use it anyway and the fact that i was going to put in petrol anyway for the new week coming, never mind the fact that i did not ask for that amount, i did not plan on spending that much, why do i have to accountability for his attendants not paying attention at doing his job and i am very angry at the manager for calling me a ***** and saying that its his attendant's word against mine, i did not ask for all of that but i have to pay for it, the police and the manager sugessting that i leave a laptop,Ipad, Hard Drive until i came back to pay it off