I have Insurance but I am not getting service!!!

On Saturday we went into the Customer Care walk in centre Sandburg. We have a PVR with a problem. Got ridiculed and made out as if we were *****. The person was rude, argumentative and had a terribly bad attitude. Priscilla was her name! Eventually after an hour she swopped the decoder. Got home it was still faulty. They all blame the installation! Went back on Sunday. Same problem! Not even the decoders they bring out to test works! I was then told to take the Xtra View to the other side and see if the decoder gives me the same problem. If it does the installation is faulty...... I did that and everything WORKS! So it is not the installation!!!!!! I have taken the decoder back again today and was given a DOWNGRADED decoder!!! Got home and the power supply of the old unit does not fit on the DOWNGRADED decoder! I AM NOT HAPPY!!! I now have to go back again!!!!! Please sort this out! I need someone in management to call me cause when I go there and ask for a manager i get told they not available!!!!!! This is absurd! DSTV you are the worst company i have ever dealt with!