Dominator Pool Cleaner not performing

My old Bull Shark pool cleaner, which is also a Pentair product has a cracked swivel joint and has cable ties and tape around the crack to make it work effectively. The unit is 6 years old. To be honest it works effectively until the tape comes off and loses pressure again. I then bought the replacement Bullshark Pro from Makro, which worked easily around walls and floors but found it was stcking onto my light fiiting and stayed there as the edge of the fitting jammed it from jumping over. I phoned makro and they advised me that it is not recommended to use that product anyway for a 8 x 5m pool, so they suggested a dominator.at R2299-00. I got a counter quote from The Pool Team at R2000-00 and purchased it from them. It does not operate to my satisfaction neither Pentair the manufacturer whom The pool team passed the responsibility to Pentair for a refund, which they refusing to honour. They blaming my installation. As unhappy consumer I want a refund/credit voucher as they unit is not cleaning the walls of my pool and is sluggish compared to the cheaper traditional pool cleaners. Contact Pentair at 011-2521019