Refused to fill my gas cylinder away even though it was still within Afrox trading hours

I'm extremely disappointed with the service that I got for the second time at Afrox Chamdor Krugersdorp just now. It was about 16h13 today when I got to the Afrox Chamdor premises hoping to get assistance on getting my 2 gas cylinders filled up. The 3 employees who didn't even want to open the gate for this other lady and I just said it's closed and everyone knows all Afrox branches close at 16h00 but the trading hours on the board were written it closes at 16h30. They all walked away leaving us like that at the locked gate after telling us that, when we requested to speak to the manager or supervisor of the branch they mockingly said there's no manager. I am extremely dissatisfied with such service and I need an explanation if this is how Afrox conducts business/ treats it customers why. I need corrective actions and I need to be updated about those 2 rude employees. I stood for a few minutes and those were busy on the gas cylinder cages as if they were still working (checking something).