Faulty Defy washing machine complaint

I bought a defy washing machine at Uitenhage ok store last year, first time i opened that machine i realized water from the water dispenser the water was mixed with dust, i reported the to ok store then sent a 1st technician to examine what is the problems, 2nd complaint whenever i wash my clothes with the machine it produces dark stains particles i logged the call to the store then sent another technician to see if there's nothing with the machine, the technician didn't see anything wrong with the machine but the machine kept on producing black marks on my clothes as a result i stopped washing my white/colourful clothes with that machine. I logged another call with the store then sent another technician to fix the matter all of those technicians didn't assist me, i went straight to the store i spoke with the store manager, the store manager was advised by the defy company to ask me to bring a sample of the clothes with the dark marks so that they can exam the marks on the lap i send the clothes sample a month ago no one assisted me even the defy company i had the worse bad customer service at ok store it's the technicians, defy consultants, ok store manager and defy service manager. I even asked the store for an exchange of machine they refused and told me defy is handling my issue not ok. Now I've been jumping up and down calling both defy and ok store with no assistance. Please urgently assist me.