Terrible attitude and response to complaint

In December 2014 I purchased two bambino high chairs from Baby City in North gate for my twins. About six months later the buckles on one of the chairs broke. About two months after that the stitching tore along the strap that ensures that the baby stays inside the chair without falling out. And a month after that the buckle on the other chair broke. So now I have to tie the straps to keep my twins safe while they eat. I took the chairs into baby cite with the slip. The lady at the front gave me no sympathy, saying that it looked like overuse. She argued with me from the beginning, never allowing me a chance to express my dissatisfaction. Finally after about 20 minutes another staff member said the rep of bambino would only be in a week later (they thought) and then he would have to send it to Durban to be assessed and that they may charge me for it. These chairs are no longer safe for my 15 month old twins to sit in while eating. I spent a lot of money on these high chairs and baby city does not care nor are they willing to help in any way. Because of the attitude from the staff I will not shop there again. And I hope that they are not recommending a brand that destructs so easily