try walking the other way , while your waiting for him your giving him the right to say where and when he goes so walk away from him call him and when he see,s your not with him he should , i say should run to follow you ,he is also still a pup so he will be very excited to meet other dogs ect our did and still do just that they will eagerly welcome others to join in play time , to some degree you should allow him to say hello as long as the other dog or dogs seem accomodating of him , as young pups often get very excited it does them good to soscialise .

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