Complaints and product dispute

Purchased a Raleigh Mountain bike for my son at the end of November 2024. Took the bike in today due to the rusting of the entire chain and some bolts on the bike. In this short space of time the returns division stated that they could only book in the bike for repairs and find an outcome from there. I explained to them that this was unfair due to the duration of which the bike was purchased and the defective workmanship on the bike. I even showed them that the bike had a small scratch and under the coat of paint was full rust, this means that Raleigh itself is spray painting the bikes or this bike which is completely rusty and selling it to us consumers at an arm and a leg. Makro itself didn’t want to swap out the bike or refund me. November till now, this means that after paying so much of money for a bike they won’t do any form of internal resolution to sort this issue out.