worst sevice and phone ever

upgraded from great s4 no problems to s6 in may this year, phone keeps switching on and off and freezing, have had phone at somerset mall, for complete reboot, did not work, was told to go to century city were they can fix while a wait, did complete reboot again, phone fixed, no? drove out of service center, not even out of parking lote and phone freezes again?? went back was told i must leave phone for 1 to 2 weeks, cant do , buisness phone, my life depends on it to work and put food on table. i pay a huge amount off money for this phone, are you supposed to buy 2 at a time just in case one brakes,?? this phone is only 5 months old. to drive from somerset west to capetown cost me, time petrol and lose of income, what are we supposed to do??. i think its time a company as big as samsung must get there things in order as there service does not come near to what they brag about.