Bad Service

I recently purchased a W206 C Class from Mercesdes Benz The Glen (from Dineo) and delivery was on the 11th August 2022. The deal included a tow bar as one of the extras that had to be bought and installed. After multiple times trying to get hold of the dealer ship about the tow bar order, I was then asked to bring the vehicle on the 23rd November for the installation only to be told later that day, the tow bar that was ordered is an incorrect one. Now the dealer ship is quite whether a correct tow bar will be order or not. I have been paying my monthly installments without fail and yet my car doesn't have a tow bar.