We buy cars refuses to pay faults on vehicle purchased

Bought a vehicle on 21 Des. On 13 January we saw an oil leak on the vehicle that was not mentioned on the dekra report and reported the matter on the same day. After numerous attempts to find the oil leak and different repairs being done on the vehicle in order to solve the problem an amount was outstanding and invoice forwarded to We buy cars to be settled. They now refuse to pay with a different excuse everytime as to why. The worst after sales service ever. Quick to sell the car but when issues arrise they just aren't as interested in you. Will never recommend to anyone and I'm taking the matter to the Motor Industry Ombud of South Africa (MIOSA)