I also say leash him! Being off leash is an earned privilege that can be earned when your puppy has been taught a reliable recall. Start proofing a new recall word or sound (I use back), in the house with low distractions. Say the word in an excited, happy manner and treat heavily for coming. The first few times, make sure puppy is already looking at you. Recall training is all about setting him up for success, not testing how well he will listen. When he comes, lots of praise and yummy treats. It's a party! As he becomes reliable in the house, take the behavior outside on a regualar leash and then to a long line.It is always exciting when puppy returns to you. Then, you can try it in an open field with no distractions and finally move up to a high distraction setting. Also, when your dog gets a reliable recall and you, for example, take him hiking or to the dog park off leash, call him to you several times, treat and release him to go play again. Otherwise, dogs learn pretty quickly that when you call them, it means the fun is over and he may feel punished. Hope this helps.