Not happy.

My son bought a kerb s****** with his birthday money 17Feb . After riding it indoors after a month the one wheel doesn’t want to turn properly and makes a terrible noise. We took it back with the receipt and was told that they can’t replace it but need to wait for the supplier to tell them what to do. It’s now been a week later and nobody can give me answers. Every time I phone I just get told that they are waiting for the supplier. Seriously.....it’s not a R5000 s****** that’s faulty. How difficult can it be....!