Bad service

I went to this petrol station yesterday around 1pm, Milmar service centre. I did not ask for a receipt as I was in a hurry and put in R200 petrol. My petrol gauge never went up and still now it has not. I went back and they told me no manager was on duty and I asked them to call the manager, which they did not do. They told me my gauge will go up but still now it has not. I told them I know my car and it would have gone up already. I'm horrified at the fact that they could not help me. I will not be going to that service station again unless they rectify the problem.