Game Stores Warranty/Guarantee Policy as per manager

So I have purchased a washing line in March 2019 and used it atleast 3 times until in May 2019 the products plastic handle had snapped. This product was purchased at the Game store in Westwood Mall, Durban. When I get to the customer service desk the manager insists that he became a diagnostic specialist by insisting we have overloaded the washing line and giving us all the possible ways it could have broken. He refused to take into consideration the customers point of view and the customers frustration of purchasing a washing line for around R600 and the plastic parts start to give up. When I had told him I demand cooperation from him as this item has a 6 month guarantee or warranty, whichever it may be. He was of no help and he was extremely rude about the situation causing an embarrassment to me. I demand that the Game store keeps up with rules of a guarantee or warranty on a product. If their policy is good enough they should atleast train their staff especially Management on how to interact with a customer. This manager at the store also gave me a scenario on how if this item was actually a defect then the entire container load would be a defect when this is not true. It is possible for a PLASTIC part to become a defect. It is really frustrating as a customer to go into a store and spend alot of time and money and get this kind of treatment in return. He also made it seem like it doesnt matter if a product has a warranty or guarantee.