Try leaving some music on (but not too loud). Make sure it’s a station you listen to often so that way it recognizes it.
(My Dogs used to bark a lot while we were gone, but leaving a country station on really helped.)
Also you could, try getting one of those toys that you place the treats in.

well, its not quite as high tech as the ‘Yapper Zapper’ but we handle crate barking in a similar way. We just keep a spritz bottle near the crate. When the dog barks we walk over (no talking or affection) and spray the dog w/ water. Most dogs will not like this. (and if your dog is very stubborn it may take a while) But this method has worked on all of my dogs.

spray him with water in his face with a spray bottle when he does that. and say “Quiet” then after a while the word alone will work.

My dog screamed and barked non stop for 2 straight weeks in his crate. Then he learned to love it and now he doesn’t make a fuss. I tell him to go in and he goes right in. I never had to use a bark collar or anything. You can never ever give him attention when he is barking. You have to wait until he is quiet.

You shouldn’t be giving him treats to try to get him to stop barking, that just tells him that everytime he barks you will give him exactlly what he wants so just ignore him.But if that doesn’t work you can always get a shock collar. They will not severly harm your puppy just enough to where he will stop barking.They can be adjusted so that you know you’re not hurting him/her.They can be cheap depending on where you go.They have them at petsmart for about 20 dollars.