Seasidesaint

Any suggestions would be appreciated I purchased a 2017 high country used less then 30 days ago. The lights for seat heaters light up but neither one heats , the cooling part of both seats are functioning as it should. I have been to two separate GM dealers one said they have no idea what’s wrong. They opened a case with GM technical support. (I was told maybe it’s to warn out ) the next day it was 28 degrees (not warm) they don’t work. So on to the next dealer an additional 159.00 to be told they think both passenger and driver side has shorted out. The truck had 20,000 miles on it . I can see one shorting out but all of them?? They can’t guarantee this 1400.00 repair will fix it. They want to replace all four seat heaters. Had anyone experienced this issue ? I thought maybe a ground was bad having an electrical background if the ground has a short they wouldn’t work.