Bad bad service.

I took my car in, in November 2018 after being in an accident. The car was "done" by 13th Desember but there was parts that was not fitted on my car. Bumper slides and mudflap at the back. They had tp replace the shock on the left and according to them they did but its still making a noise. Every time i phone them or go see them they say they cannit do anything they are waiting for GWM to send the parts. This is now almost a year and now my front bunper is starting to peal at places. And the back bumper is not fully fastened because of the bumper slides so it rattles the *****s loose and the *****s is starting to scratch my cars boot now. Very bad service from leons and from gwm