Carrier/rack problems of the 2016 GMC Canyon

All my dash lights keep coming on and alarms going off. The poer steering, abs, check engine, stability track, parking brake, brake, etc. If I pulled over and turned the vehicle off to get this to stop nothing works when I crank it up. I have no power steering. If I crank it a couple times everything goes to working. Then a few miles it all starts again. This has been going on since April. I have put it in shop in April, the dealer couldn't get it to duplicate, in may, same thing, in June they finally got it to duplicate and changed a module. I drove it 772 miles it started again. I carried it back in July they said GMC said it was a steering gear. I got it back at 336 miles it started again Aug. 2nd, it did it again at 798, then 813 miles on 8/9. I carried it back they supposedly found a rubbed spot in a wiring harness and fixed that stating they believe it is fixed. I contacted GMC in July trying to get them to take this truck back, they said they couldn't do that but extended the mfg warranty out to 100000 miles. I bought the truck used with 16000 miles on it still under mfg warranty, all the problems started at a little over 34500 miles. I fear for my safety as well as other due to steering wheel locking up. I mentioned this to GMC as well. Is there anything I can do to get GMC to take this vehicle back? I can get paperwork from dealer if needed. Is there anything you can do with this? I had a case # with GMC when the gave extended mfg warranty 9-5383131610. I talked with a representative name martin phone # 866-790-5700. Ext. 5915657. I left him a message on 8/12, he is yet to return my call.