Hi can anyone help. I have an old fiat punto and im having trouble getting a bike rack to fit. I bought one from Halfords but it kept coming off the back bumper-my car has a slopping bumper. I just got one from Tesco direct but that will also have to go back as its not suitable for the car although it didnt say that on the write up. Any ideas please. Im new to cycling so not sure where to go. Many thanks for any help you can give me.