Homechoice debt accumulation with an incomplete product

In 2021/06/04 I bought an Allure 20 piece Essential Dinner Set: Platinum at Homechoice but I received only 16 piece and when I complained on several occasions they promised to look at the matter but didn't, the dinnerset was worth R4763,99 but now because of two payments that I missed I ended up paying more than R7500 still today I haven't received the 6 piece that is owed to me and I'm blacklisted and I'm still paying for the dinnersets at an agreed rate of R500 per month is this fare?