Cash Back - True or faulse ?

Last November I invested in 4 BF Goodrich all Terain tyres at a cost of $1087, the influence in buying them was the $50 "Cash-Back" offered. After filling in the nessassary coupon and mailing it back with the purchase invoice and waiting two months, no "Cash Back", Three phone calls later, nothing, The point I'm making, DON'T RELY ON THE GOODRICH CASH BACK DEAL. IT WONT HAPPEN.