Utterly disappointed in BMW SA

I recently purchased my first BMW, a 140i from Donford BMW in Stellenbosch and I was overwhelmed with the initial excellent service received from the team. After a few days, I started noticing a vibration when travelling on the freeway. I then returned to Donford with the vehicle to sort out the issue (they balanced the tyres) but when I left the dealership I noticed the vibration again. Upon my return the second time I noticed the 'balancing weights' had fallen off which Donford BMW supposedly re-balanced when I initially returned that car. After my third visit to the dealership regarding the vibration they decided to replace two rims of the car with another vehicle on the floor’s rims, yet the vibration persisted. I returned the vehicle once again and the head foreman found a nail inside the tyre to which his response was that the tyre was slowly deflating over time causing the vibration - Donford decided to replace the back tyre which they made very clear how it hurt their budget. I expressed my concern as to why the tyre pressure notification did not appear on the vehicle and he could not answer me. I was very concerned, as this has now become a safety issue. I then experienced the same problem after the tyre had been changed and requested they sort it out once and for all as this would now be my fifth visit. Donford said the have a Regional Manager down from BMW South Africa and they would like him to give a second opinion. The mechanic confirmed that himself and the Regional Manager from BMW South Africa could feel the vibration, however neither of them could/can identify the issue. I received my car back with different tyres and rims and thought it was a joke of some sort, but to my dismay, it was not. I was asked to test the vehicle like this for a week, however there was no difference with regards to the vibration. I then called the Sales Manager at Donford to express my concerns and he simply said it’s out of his hands and it’s the workshop forman’s issue to deal with - which I find very unprofessional as the vehicle was sold to me by him. Drove there AGAIN yesterday for the 6th visit (22/03/2019), for them to put my old rims back - vibration still there but this morning I found another surprise… my entire windscreen is loose now too!

I have been very patient and accommodating during the numerous visits to Donford Stellenbosch with a second opinion from BMW South Africa and simply no solution other than putting unnecessary mileage on my vehicle (of which I have a limit) and basically using it as a test case. I am utterly disappointed with the experience I have had with BMW. I moved to the brand due the premium, elegant and sheer driving experience, however I seem to have been mistaken.

Clearly the vehicle which was sold to me is faulty and is a safety risk. It clearly needs to be replaced however there is a huge lack of urgency/concern from BMW South Africa as well as Donford BMW.

I continuously logged all these issue with BMW South Africa to keep them updated with regard to the situation however to date still not solution.