Is BMW becoming Chinese quality?

My car BMW320i used to be serviced under the motor plan at JSN dealer in William Nichol, Bryanston, Sandton, Johannesburg. Back in November 2017 we noticed that the oil level is going down. We reported the car to JSN who claimed they fixed the problem. A month and a half later in January 218 the oil lamp came back and again JSN kept the car for couple of days then said it was fixed. Two months later on the 14 March 2018 the oil lamp came back and we took the car to JSN who gave us an appointment few days later. When we dropped the car for repair they said the motor plan has expired. We discovered that the day we took the car to JSN to report the oil fault was the last day of the motor plan. We complained that the fault has been in the car since November 2017 and they failed to repair it properly. We contacted BMW at that time and JSN had to do the repair. At that time they told us the repair is guaranteed for six (6) months. Again two month later oil lamp turned on and we checked oil was low. Talked to JSN who took the car in yesterday for checking. They called yesterday afternoon to claim that the oil leak is from different cause than the previous three repairs. They said the cost of repair would be ZAR 21,000 and they will share the cost with us paying ZAR 8,000 therefore we should pay on ZAR 13,000. This was unacceptable to us as they should have checked the entire oil circle the previous times they took the car for repair. We said that this is BMW not a cheap Chinese car that every month there is a new fault at the same area.

I’m writing to you to report such violation of the motor plan and request full repair of the oil leak. But insist no repair at JSN as they either lack the knowledge and profitability to repair the car or they cheating costumers.