Defy washing machine from Pick & Pay faulty

I bought the washing machine from Pick & Pay in Dec 15. From day one the washing machine has been faulty. I reported the fault to P&P and they said I must have a Defy engineer come and look at the problems. He came four weeks ago and still the machine is the same. He now wants to come and replace the computer board but this is not going to resolve all my issues with the machine and I will still be in the same situation (a faulty machine). I have requested the machine be taken away and I am happy to pay more money to have this issue resolved but they are refusing. How can I pay the full asking price for the machine, received faulty goods (five issues with the machine) and be told point blank they will not take the machine away! I tried to complain to the Defy manager Farnie De Young and he told me it was not the Machine that was the issue!