Bad Experience Buying A Stove

I purchased a Grundig stove at Hirsch's Umhlanga on the 8th October 2017. I had the stove connected the following weekend and found a problem. I contacted the store on Monday the 16th October. A tech responded on the Wednesday and had a look at the problem. He returned the next day with a replacement but the problem still persisted but on the opposite end of the stove. I was told that the original unit would be taken back to Defy for testing. The next day i was told that they could not see what was causing the problem and they needed someone else to have a look at the stove. I was not contacted by Wednesday the 25th October so i called the store to find out why. i spoke to the store manager and she followed up with Defy. I was then told today that they have a faulty batch of stoves and my stove will only be replaced on Tuesday the 31st October with no guarantee it will work. I now have a stove which i purchased 18 days ago for a lot of money but am still unable to use the unit fully as yet. Talk about a nightmare situation...........