Poor quality of winter tights / Wrong sizing

I bought a pair of black opaque tights at the cost of R49.99 from a Mr Price in Greenstone Mall. Literally wore these the very next day and realized during the day they tore on just the one toe! With my slip I took them back to a Mr Price store in Sandton City, your supervisor did not even give me a 2nd look she just told me “we don’t change underwear “ I was hoping to swap them for another pair of tights that were made out of wool with the hopes that the quality would be much better. Anyhow without wanting to cause a scene for R49.99 I decided to pay for the new pair of tights that would now cost me R69.99 as I had already brought these with to the till point - total spent at your store is now R119.99 which I really didn’t mind, here is my frustration the new pairs tights size were supposed to be an XL and the previous pair was a L. The next day I put on the XL new pair and guess what they literally couldn’t even go up my hips! Obviously frustrated that I’ve now visited your stores twice to get what I want and I keep getting disappointed as my expectations aren’t met as a customer! There’s not a chance these tights are an XL as I was already taking a size bigger to begin with now that these tights aren’t even the right size I don’t even want to waste another trip to your stores because I know the answer already. I’ve now had to spend another money with a different brand to buy winter tights that fit me well. I need my money back please for both these tights as I cannot use them for the purposes I bought them for. I am not exchanging them I’m returning the one for terrible quality and the other one for incorrect sizing written by the factory on the packaging! I will not be buying winter tights from you as you’re not offering me value for my hard earned money. Also, you need to take these issues up with your suppliers not to mislead customers with sizing and to offer a much better quality! Other tights I bought from other retailers are perfect no complaints with them.