I feel your pain.... Nip it in the budd asap !
It will only get worse. All four of mine do it. I have tried everything, but waited too long to try. Well in my defence I have to admit I didn't find out about it right away. And it was too late when I did.
I've tried pineapples, bitter tabs correction commands nothing works. Hubby is on a strick poo clean up schedule so that they dont have anything to eat when they go out side to potty.
It like a constant recycling. Sure when its for paper and plastics not so much for dog crap!
