Bad service at Dis-Chem Soshanguve Im called unhygienic while they are clean

I bought a ***eon Manuel breast pump on Friday the 10th of September 2021 ,I tried to connect it as per instructions the pump doesn’t walk , I went to Dis-Chem this morning with everything still in place and I was told that they can’t take it back for hygiene reason I told the guy what hygiene it hasn’t worked it doesn’t work the same person talking about hygiene tests the pump on his arm says it works fine.. now I’m must take it back use it while he tested on his arm because he’s clean and I’m not and go back and attempt again while it doesn’t work . I’m stuck with a useless product that costs me R800 and it’s not working I’m so disappointed with Dis-Chem