Disgusting service at SHELL SOUTHGATE

Hi my name is Kim, I am utterly disappointed with the service I am continuously receiving from the Supervisor at The Shell Garage at Southgate mall. The first encounter I had with the manager named Moses was the day the petrol attendant put Petrol instead of Diesel in my vehicle.. when the incident occurred I asked if I could see the manager, the supervisor which is Moses then came to me and said to me there is nothing he can do but call his manager to find out the way moving forward, at that point I was already very upset because he did not even acknowledge the fact that there is a problem, secondly he didnt even have the decency to apologize for the inconvenience caused. I had to wait a whole hour for their technician to come and attend to is in order for them to drain out the petrol they put into my vehicle, while waiting the Supervisor did not check on us, still hasn't apologized but his a supervisor... nonetheless after a whole 3 hours they finally did what they had to do. A week ago I went to the same garage put in diesel and was about to pay for the diesel, the petrol attendant then tells me that I cannot pay with an incentive bank card that mind you has a chip where I can even draw money from. I then informed her that I always use this card to pay and have no other card to pay with, once again Moses the Supervisor at the garage was assisting another customer at the time, overhead our conversation and tell the petrol attendant that I have no other choice but to pay with cash, I asked the lady please inform Moses then when addressing customers he needs to do it in a proper approach not scream over another customers vehicle and address the matter... Moses at the time comes to the car and says to me as I QUOTE "I HAVE TOLD YOU THAT WE DO NOT ACCEPT THESE CARDS ANYMORE AND YOU SHOULD NOT MAKE YOUR PROBLEMS OUR PROBLEM IF YOU DO NOT HAVE CASH ON YOU, YOU PEOPLE THINK YOU KNOW TO MUCH" I feel for a Supervisor he has no work ethics and no morals because he addressed me like that infront of the petrol attendant that's below him, how does one lead by example when he has such a disgusting attitude. If he does not know what customer service is then he is definitely in the wrong department!! Pathetic service from a SUPERVISOR CALLED moses