Selling broken televisions and sending techs to fix brand new TVs

My elderly aunt bought a 65" TV from Makro. Not too long after that the TV started showing lines across the TV. We called to report the issue and they said they have to send a technician to fix A BRAND NEW TV. He fixed the TV The lines are now back again. So basically, Samsung is selling broken TVs to its users and sending technicians to fix their mess, hoping the problem doesn't come back or that it works till the warrantee is over so that the customer is liable. I have been trying to call for 2 weeks now. The contact center keeps saying that they are calling me when no one is contacting me. They closed the first Ref number. The second number is