Bad service

Good day My name is Akani Macheke, I bought 4 pairs of Levi's jeans at mall of Africa outlet 28 Nov 2019, I don't know what happened but I fitted the right size but when I get home I have size 27, I went back for exchange the following day, they said the don't have sizes I have to come back next week Friday as they receiving stock in Thursday, I did so, next week Thursday I went back again, still no size and advised again to come the other following Friday, I did so but that time was send to crest mall, I went to crest mall on the 14 Dec 2019, at Cresta mall still they don't hv sizes, the also send me to Sandton, I went to Sandton 16 Dec 2019 when I get there they said to me they can not exchange them because I bought them on 40%off so they are going to lose out, I called mall of Africa branch while still in Sandton unfortunately no answer, I drove to Mall of Africa same day, they said to me Sandton branch they were supposed to exchange them for me bcoz either way they were going to sell them with original price, now am sitting with big size jeans on top of that I spent lots of money by traveling to 3 malls as per their adviced