2015 MOBILITY WORKS CHEVY EXPRESS 2500 Electronic Stability Control Esc Problems

I PURCHASED THIS VEHICLE USED, HAVE HAD AN ONGOING PROBLEM WITH THE "STABILITRAK SERVICE" LIGHT COMING ON, HAVE HAD IT INTO THE SHOP "AUTOTIRE" FOR SERVICE 2 TIMES, THEY HAVE REPLACED THE "STEERING WHEEL MOTION SENSOR" AND HAD THE "ANGLE SENSOR" NEITHER HAVE FIXED THE PROBLEM. WHILE THERE IS NO RECALL FOR THIS THERE SHOULD BE, SOUNDS LIKE A DESIGN FLAW WITH NO APPARENT SOLUTION, THE "SERVICE STABILITRAK" LIGHT COMES ON ALL THE TIME, NO MATTER IF VAN IS SETTING STILL, DRIVING, EVEN IN PARK. I AM NOT REAL SURE WHO TO CONTACT WITH SOMETHING LIKE THIS WITHOUT BEING CHARGED HUNDREDS IF NOT THOUSANDS OF DOLLARS, HAVE ALREADY HAD DOWNTIME AND APROX $500 IN COST ALREADY. THIS IS SOMETHING THE GM SHOULD FIND THE FIX AND RECALL, I SEE THERE ARE MANY VEHICLES AND MANY YEARS INVOLVED. WE USE THIS FOR OUR COMPANY AND TIME IS MONEY. THE DATE LISTED...