Poor Customer Service

On the 14/12/2015 between 6:20am and 6:45am I waited for just about 5min for an attendant to come and assist me with pouring gas into my car. Another car arrived after me (Mercedes A class SLD619GP)and I was surprised that the petrol attendant went to the other car and assisted the lady in the car instead of assisting me. I was highly offended to a point where I thought that it was because I was a black person and the lady that arrived after me was a white person. I then proceeded to escalated this to the supervisor Tim who tried to assist by asking Willy why he did that and all I got was a sorry he never saw me yet he was able to see the other car parked next to me?. This has happened twice at the same filling station and if the service there order of service is based on the color of my skin, then I need Engen to clarify that so that I no longer fill up at Engen.