2016 BMW I8 Tires Problems

I PURCHASED PIRELLI P ZERO SUMMER SPORTS 245/40 IN THE REAR AND DROVE ABOUT 300 MILES SINCE, AND THEY LOOK WORN-OUT AND THE CAR SLIPS PRETTY BAD IN THE RAIN. JUST AFTER PURCHASING THE TIRES ON A RAINY DAY ON THE HIGHWAY MY CAR SPUN OUT ALMOST RAN INTO THE MEDIAN. WHO WOULD HAVE THOUGHT THAT BRAND NEW TIRES WOULD WEAR OUT SO QUICKLY THAT IT WOULD BECOME SLICK IN 100-200 MILES WITH NORMAL DRIVING, NO TRACK, NO RACING? PIRELLI OR DISCOUNT TIRE IS NOT TAKING THIS SAFETY CONCERN SERIOUSLY AND IS ONLY STALLING. I HAVE CALLED 6-7 TIMES AND THEY KEEP TELLING ME TO CONTACT THE DISCOUNT TIRE, AND DISCOUNT TIRE SAYS I NEED TO CALL PIRELLI FOR MANUFACTURE DEFECTS. *TR *BF