Factory fault on jeans

Hi. I got 3x pairs of jeans from Edgars 2 weeks ago. I tried them on and they were fine. I swapped the 1x pair out for the same style, colour, cut and size but just to a new pair as the ones I tried on had a faulty zip. The new pair that I swapped I didn’t then try on as it was (supposed to be) the exact same. The pair of jeans is soooooo small on the knees and the seam at the back, down the middle is skew. I already removed the tag and threw it out when putting the jeans on and I had to then wear the skew, highly uncomfortable jeans for the whole day since I packed only those for after gym, expecting them to be fine. The knee are is abnormally tight and I’m sure it is a factory fault . I am very angry as I saved for a while to make the purchase and now I cannot return or exchange them…..