How long have you had the puppy? maybe you need to give the older dog more time away from the new dog by using an ex pen for the puppy. Is stu marking his territory? If that is it you could use belly band. I think if it were me I would get an ex pen for the puppy and start over with the interacting and only limit it for short periods at a time.
When I got my puppy I had an older dog and I had and ex pen and I did not let them interact for the first week except by sniffing each other through the ex pen or if I was holding the puppy I would let the older dog come over and check her out.
As time went on I would use the ex pen for the puppy when she was annoying the older dog too much. It has been almost 4 yrs and they are best buddies
