Bad service received

I sent my husband to link pharmacy on 31/01/16 to buy an ontiment instead he was given a wrong product, I went there today by 2:15 because I stay in Randfontein but I was told that I can not get assistance because the staff member I spoke to over the phone on the day of purchase she's on leave I should come back when on Saturday when she's back and she will have to buy the product out of her own pocket as per Mami supervisor of the pharmacy she can't take a decision but she's a supervisor