In my experience some dogs are motivated to do whatever behavior trick to let you know they have to potty. Other dogs aren't interested in that particular game. The best way I know to teach that trick is every time you let the dog out to potty, if he hasn't rung the bells, when you go to the door to open it, you ring the bells first and say "potty!" or whatever your command is. I also had a friend who would bait the set of bells with a dab of peanut butter when the dog wasn't looking. That encouraged the dog to lick and therefore ring the bells more often. However, for a while she was having a few false alarms because the dog only wanted the peanut butter, didn't have to potty.

Yes, a dog has a very short memory for most things. And yours is still a very young pup. Give it time and have patience. Since the time he has left the litter and mom he has learned to drink water from a bowl, eat from a bowl, sleep without any littermates, has only humans to play with, and he tries to please you by eliminating outside. I think that's a lot for a couple of months worth of trying. Keep working on the skill, but give it time.

 

It sounds like he is doing very well considering how long you have been at it. Remain patient and keep working with him. It will pay off in the end.