Paying so much and it doesn't last

Good day. I did not want to result to this but your customer service is not responding at all. I bought a pants at pick 'n pay clothing on the 01-10-2022 for R209. I had it on once. I also bought other clothes from other stores. On the 3rd I washed al the clothes and the pick 'n pay pants the seam came loose between the legs. I am very upset as for its not a cheap pants. I still have my slip. Can anyone help me. The other clothes is a lot cheaper and they didn't give me any problems.