Boni baby walker

On the 01 May 2019, I bought a baby walker (Boni) for R399 at Toys r Us pietermaritzburg midlands mall. On Saturday the 04 May 2019 the child was on the walker and it broke and the child fell. I took the walker on Monday back to the shop and they told me the manager was not in on that day and I should left my details they going to contact me. They didn't contact me and I contacted them back, the manager was very rude saying that he did access the walker and it transpired that I pushed the walker because of lack of knowledge and that I should go to another shop and buy another one and then he put the phone down, I phoned again and he didn't want to speak to me agian. I phoned the call centre and spoke to Preya she told me that there's nothing that they can do because the manager told them that we pushed the walker. I went to the shop agian the manager by the name of Janette was very rude she shut the office door at us and said we should do anything we want she won't give us a refund or another walker. It's my first time buying at Toys r Us and I'm so disappointed by the service I received