Ryobi Line Trimmer 1000w Return

I purchased a Ryobi Line Trimmer of Builder's Express Pinetown on the 19th of August and return it on the 19th of October because the head stopped spinning. They sent it to Ryobi to be assessed and now want to charge a repair fee. This is ridiculous as it is still under warranty and within the first 6 months of purchase! Not only that, but Builder's made me have to deal with Ryobi directly. As the reseller, Builder's should at least guarantee the quality of the products they sell, and fight for their customers!!! I have also reviewed Ryobi at link below:

https://www.hellopeter.com/ryobi-durban/reviews/ryobi-line-trimmer-1000w-broke-charging-for-repair- **********

I hope this is resolved soon. I will not be paying for repairs on an items that was only used twice!