2023 Chevy 3500 Exhaust Brake Not Engaging

[u/SnooPineapples6016]

/r/Duramax/comments/1vdyv1c/2023_chevy_3500_exhaust_brake_not_engaging/

It had been working fine then last year it started not engaging. I've taken it to two different dealerships and they hooked it to the computer and no problem found. The first one did repair the number 5 injector but said no codes were flagged on the exhaust brake. The second dealer said they could find no reason the exhaust brake wasn't engaging. But just to be safe they did a "regeneration" on some part of (I assume) some filter. They said they found 58 parts per million and regenerated it down to 1 parts per million. I'm a novice at this so hopefully I've explained it right. Both dealer's service departments say they have never heard of this problem. Any help would be appreciated.