Hisense after sales

My Hisense fridge broke in September 2019, the technician fixed it within a week, which was great. The fridge broke within the 3 month guarantee. It has been 3 months and I am still waiting for the technician to come and fix my fridge. His excuse is that he has transport problems and recently he says that Hisense doesn't have the parts to fix the fridge because they don't have stock. I have been without a fridge for 3 months now and still waiting. The technician doesn't answer my calls - I have to phone from another number in order for him to answer my calls!! I phoned Head office Hisense and they say he is the only technician for my area. What must I do??? Is this how Hisense operates?