2015 Chevrolet Silverado 2500HD - Phantom Trailer Electrical Problem

2015 Chevrolet Silverado 2500 4X4. Driving down the road and Trailer light flashers on trailer braked or engaged ( I am not pulling a trailer . I pull over and stop and restart the engine and it is good for a while until the next time . Has anybody else had this problem ? Cal the Dealership and they can’t test it if it is not doing it when I take it in .

Could you explain that a little better?