Brand new Defy Stove defective on many levels.

We purchased a Defy Kitchenaire 620 stand alone black stove from OK Furniture, Pinetown branch. We paid R 3 999, on a black Friday special. From the moment we opened the packaging we had problems with this stove. The warmer wasn't aligned and therefore could not be opened. Every single switch on the panel was defective: Lose, not turning, when we turn it goes past the number etc. After several calls the stove a technician came out on 4 Jan. 2020. He was a very pleasant gentleman who did his level best to fix the problem concerned, but we are still not entirely happy. However, on Saturday 11 Jan. 2020, we attempted using the oven for the first time. To our horror, a roast lamb that was meant to take about 2 hours to cook, took an entire day. The oven is not sealed, and there are large gaps of about a centimeter on either side and on top. As a result the air is going straight into the oven. The oven kept switching off. In addition, the solid plates are not operating normally and not heating effectively. We have lodged another complaint with Defy, but nothing has been done. We are at our wits ends with this stove, and we would like a replacement immediately. It is clear that this stove is defective and has several factory faults. We are not prepared to keep a stove that we purchased brand new in this condition.