Guarantee on new product

I visited Paarl mall store to exchange a broken kettle. I was told that although the replacement is new, no guarantee will be offered on the replacement. The kettle had a 2 year guarantee, which expires in 2020. According to the manager Braam, I will only now have a guarantee of 8 months, even though the kettle box states guaranteed for 2 years. I returned home with the broken kettle, I will have to exchange the kettle, I feel the fact that the guarantee is not fulfilled as a new product is unfair towards the customer. Please advise on my way forward. I need to exchange the kettle, but can't understand why the guarantee is not renewed.