Unhappy Game customer

I am at Game store thohoyandou I bought a bycicle on the 9th February 2022 and it was broken last week so I took it back today they tried to fix it but they failed and told me to talk to someone privately who works there that can help me after hours and I will have to pay him,they didn't even ask to see my till slip.so now m stuck with worse broken bycicle.i even took a pic and a video of them dismantling and assembling the bycicle there 3 guys.