NHTSA Complaint #11458798 — 2016 GMC SIERRA 1500

I purchased a certified pre owned 2016 sierra slt in February and just after a month of owning it a notification started to pop up and chime on my dash stating "SERVICE TRAILER BRAKE SYSTEM". I have had my truck in the shop multiple times after to have this issue repaired and nothing has worked. They replaced the dash GM Genuine Part 84108373 break controller switch and buttons, the GM Genuine Part 23337305 trailer brake control module as well as the 7/4 pin 23404450 GM OEM Trailer Tow Receptacle. Nothing has fixed this issue! when the truck chimes I lose my trailer breaks and this is extremely dangerous hauling a camper weight 6500lbs. I also lose the ability to make phone calls, hear my blinker also the radio. This renders my truck inoperable and a danger to drive.