BOSCH DIESEL CENTRE CENTURION ********!!!

I took my car as it was smoking and they advice me to Book it in for a full “exclusive diagnosis “ of which I did and later they called to say the problem is the injectors then I Adviced them to proceed and fix them and I asked if this get sorted will the smoke go they said definitely Apon collection of the car I find the car is still smoking and I showed them they said I should bring again when I get chance and I did and 3 days later they say there’s something wrong with the engine and it will cost me 38k on top of the 8K I paid