Very angry customer!!

i bought a hisense U962 for R899 it had network problem and screen went blank time to time with in 8 days took the phone to repairs on the 25 January 2019 till this day i haven't received my phone i am very angry as i bought this phone because i needed a phone so bad, how could Hisense sell their phones when there were not properly checked if they function well its impossible that the phone gets broken within 8 days and till today i don't have a phone i am very upset and fuming because that means they don't care about their customers and reputation , 2 weeks back i sent an email complaining about this matter then some lady rep**** saying they cant track my phone where as MTN said they took the phone to hisense