After service (warranty claims) GMSA

If registered a complaint on 31 August 2019 with ref no "SRNO:***" regarding the motor warranty of my opel astra as I experienced problems with my car and when i've registered the complaint the dealer they indicate to me that the warranty has expired. On checking the date of purchase etc this was not true. I've tried to raise this complaint with GMSA but is not getting any assistance. It seems when you buy a car (opel) you will not get any after service because they have withdrawn from South Africa. Very poor services for opel brand names.