phone complain

i bought NOKIA 3 on November 1st , this phone started giving me problem overheating , doesn't get full and ink from screen , and i return it to the dealer for repair which costed R788.8. i made that payment and my phone return back to me , after two months i started to show one and the same thing . i return it to the dealer again on 4 of september 2018 and as from there i don't get any feedback about my phone when i call them by myself the keep on telling me that there are phoning technician . i feel like i bought phone from Pakistan show or something why there never call me and inform me what is going on , this phone is having factory fault i cause it keep on giving me same problem . now i need new phone or my cash back i cant deal with this MTN anymore