Terrible quality and bad customer service regarding leggings purchased

I have purchased two leggings from KoaKoa Active and have worn them less than 7 times in total. They claim that they have durable performance/active wear and they are not cheap at all, with a pair of leggings being priced around R800 each. I had a light fall and my black pair tore so easily. My other red pair is coming loose at every seem possible. I have informed them about this and the poor quality of the leggings but they are not able to provide me with a replacement or a refund and appear to be sarcastic throughout the entire interaction. I am utterly disgusted at this brand and the lack of integrity or care and feel that they are selling a product under the pretense that it is of a high quality when in actual fact it isn't. They have no way of dealing with customers and give local companies a bad rep